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BjornF16
06-08-2012, 09:50 PM
I don't have a good mount on my Satern Spartan Grendel for bipod, so I've been using a "bench rest" set up (poor man style).

My shots have a tendency to jump right. After the shot, my scope has jumped right (mainly) so I'm pretty sure it is something I'm doing or the setup I have. I've attached photos of the bench setup. Bags are leather.

Today I was taking 5 shot groups before reloading the 4 round hunting mag. I didn't reposition other than fine tuning aimpoint within the 5 shot groups. A couple of 5 shot groups were tight, and it felt "right" (gun recoiling back, no left or right jump of the scope). But repositioning after this grouping would result in the jumps to the right again. I was shooting both factory and handloads. The handloads have tighter SD and ES than the factory rounds.

I'm considering getting a decent front rest, but don't want to spend $500 for a high end benchrest mount (any suggestions?). Leaning towards leather/cordura combo bags (cordura for less resistance?).

I've also bought a book by Tony Boyer on Rifle Accuracy. While mainly geared towards benchrest bolt actions, I figured there has to be some techniques that would apply.

Here are some suggestions he makes if impacts are "jumping right":
1. "palming" with right hand when squeezing trigger
2. Leaning cheek onto stock while sighting and then letting off at shot (I think I may be doing this)
3. Leaning into rear bag during setup and then letting off at shot (not sure if I'm doing this or not...I am squeezing rear bag for elevation control and pulling stock into my shoulder during sighting.

Some indications for impacts jumping left:
1. Leaning cheek into stock at shot (I have a few of these I believe).

Not sure if my equipment is contributing to the errors above...any suggestions would be welcome.

My current game plan is to get a front rest and different rear bags and hit the range at 50 yds with .22 LR for practice, but the recoil would be missing...


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bwaites
06-08-2012, 10:05 PM
If you really feel you are losing shots right, then there a couple things that come to mind.

1) Trigger squeeze. Depending what part of your finger is used to depress the trigger, you may be pushing the barrel right.

2) Changing cheek pressure, as you noted. I try to think of the trigger pull as a complete action. With a two stage trigger its:
1) Trigger through 1st stage to stop.
2) Trigger through 2nd stage to ignition.
3) Trigger back to reset.

In my mind its a little bit like a dance: one and two and three, then I look for the shot.

With a single stage its:
1) One through ignition.
2) Two back to reset.

The dance is: one and two, then I look for the shot.

This is not new from me, its my intepretation of something I learned from one of the top 3 gun guys in the country, Pat Kelley. (If you don't know Pat's history, the guy is incredible. He shot 3 Gun Heavy, which is .45, .308, Shotgun, open sights. He was NEVER beaten at any level: Local, State, National. Think about that! How many people have NEVER been beaten at their chosen endeavor?) He has since switched to a different category, because it got to where no one would shoot against him. He taught it to me regarding pistol, but I think it applies at least as much to rifle as pistol.

What this routine does is make you think through your follow through, which to many of us don't do. Most of us squeeze and start looking for the shot.

3) Are you squeezing the back bag? If you are a bag squeezer, (I am) the tendency is to relax that hand as you pull the trigger, and that causes inconsistency problems, too.

Those are my immediate thoughts.

BjornF16
06-08-2012, 10:41 PM
I have been squeezing the rear bag.

I'm not really sure how firmly I should be planting my cheek onto the stock or how firmly to pull in into my shoulder. I think I am being inconsistent with both.

I also noticed that the rail cover on the bottom of my PRS stock was moving forward during the 5 shot groups (I noticed after the grouping was finished). It would be nearly off after 5 shots from the recoil driving backwards, but the rear bag grabbing the cover.

Using the tip of my finger for trigger pull on the 2 stage SSA-E...the best groupings were when I was completely surprised by the discharge, versus anticipating the shot. I don't believe I was blinking today. Not consciously thinking about resetting trigger.

ricsmall
06-08-2012, 10:45 PM
i agree with bwaites, especially on the bag squeeze. I am a squeezer, and I have caught myself releasing tension at expected shot. I realized it when I went from my rifle to a buddies gun, his trigger was heavier than mine and I caught myself. mental toughness is a huge part of successful shooting. By all means, practice with a .22, .223, or whatever you need to address the fundamentals and get your mind right. Once the lump on your shoulders is working, the rest should be easy.

bwaites
06-08-2012, 11:31 PM
I have been squeezing the rear bag.

I'm not really sure how firmly I should be planting my cheek onto the stock or how firmly to pull in into my shoulder. I think I am being inconsistent with both.

I also noticed that the rail cover on the bottom of my PRS stock was moving forward during the 5 shot groups (I noticed after the grouping was finished). It would be nearly off after 5 shots from the recoil driving backwards, but the rear bag grabbing the cover.

Using the tip of my finger for trigger pull on the 2 stage SSA-E...the best groupings were when I was completely surprised by the discharge, versus anticipating the shot. I don't believe I was blinking today. Not consciously thinking about resetting trigger.

The rail cover on the PRS is a bone of contention for all of us that use the stock. Magpul should have figured out a fix for it a long time ago! I've hot glued mine to keep it in place, but that creates an issue if you want to take it on/off to mount something. The hot glue works its way loose over time, so it doesn't damage anything and it isn't permanent, but its a stupid, poorly thought out issue.

Face/cheek pressure is a personal and gun thing. Some guns seem to like more contact and weight on the butt, others less. I barely rest on my 7mm WSM, although I have it firmly against my shoulder. I tend to hold my AR's a bit tighter, but the 28" seems to actually like being held like my 7mm the best.

One thing you might try, just for fun, is to set your rifle up so that the only point of contact is your shoulder behind it and the trigger finger. That means the crosshairs are centered without you touching the bags. This creates an almost free recoil situation, so be aware the gun may jump and move a bit. See if the shot goes to the center of the crosshairs or not.

Looking at your target posted above, I would say that you may also need a little better zero on your rifle, but that might simply be that you are consistently pulling it right as you fire.

Are those 1" squares? If so, I would strongly consider trying a different bullet. You're getting a spread of 55 FPS, but you could probably tighten that up with 123 Amax's and the Amax's seem to shoot good in everything. The other 2 bullets I'd try would be 120 SMK's and 120 Nosler BT's which both seem to shoot well in everything.

BjornF16
06-09-2012, 12:05 AM
They are 1" squares. I was in the process of load development. The other two loads had 32 and 38 fps ES for the 10 shots. I'm looking for a deer/elk round...

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LR1955
06-09-2012, 12:43 AM
I don't have a good mount on my Satern Spartan Grendel for bipod, so I've been using a "bench rest" set up (poor man style).

My shots have a tendency to jump right. After the shot, my scope has jumped right (mainly) so I'm pretty sure it is something I'm doing or the setup I have. I've attached photos of the bench setup. Bags are leather.

Today I was taking 5 shot groups before reloading the 4 round hunting mag. I didn't reposition other than fine tuning aimpoint within the 5 shot groups. A couple of 5 shot groups were tight, and it felt "right" (gun recoiling back, no left or right jump of the scope). But repositioning after this grouping would result in the jumps to the right again. I was shooting both factory and handloads. The handloads have tighter SD and ES than the factory rounds.

I'm considering getting a decent front rest, but don't want to spend $500 for a high end benchrest mount (any suggestions?). Leaning towards leather/cordura combo bags (cordura for less resistance?).

I've also bought a book by Tony Boyer on Rifle Accuracy. While mainly geared towards benchrest bolt actions, I figured there has to be some techniques that would apply.

Here are some suggestions he makes if impacts are "jumping right":
1. "palming" with right hand when squeezing trigger
2. Leaning cheek onto stock while sighting and then letting off at shot (I think I may be doing this)
3. Leaning into rear bag during setup and then letting off at shot (not sure if I'm doing this or not...I am squeezing rear bag for elevation control and pulling stock into my shoulder during sighting.

Some indications for impacts jumping left:
1. Leaning cheek into stock at shot (I have a few of these I believe).

Not sure if my equipment is contributing to the errors above...any suggestions would be welcome.

My current game plan is to get a front rest and different rear bags and hit the range at 50 yds with .22 LR for practice, but the recoil would be missing...


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Bjorn:

Why would spending a bunch of money on a bench rest all of a sudden make your performance improve?

You saw how taking your shots sustained fire worked. It is because you knew you were to take another shot and thus had a more secure and solid position for your string.

And, for the good strings, your attention was focused on attaining a good sight picture for each successive shot. By having a solid, hard hold, you were more confident in your sight picture as the recoil didn't knock you out of position between shots.

Seems to me your process goal ought to be on attaining the same degree of control over your rifle after getting out of position. That one is easy to work out. Shoot five, stand up, walk around, sit down, and get back into position.

Your end state is attaining the same degree of control and confidence so if you have to adjust things in order to get the same degree of control and confidence, adjust things.

What is important about position is consistency of control and when you shoot sustained fire, you best exert quite a bit of control or the recoil will knock you out of your position. Tight, firm, confident hold where you know you are in control.

Dominate the rifle.

LR1955

BjornF16
06-09-2012, 01:49 AM
Why would spending a bunch of money on a bench rest all of a sudden make your performance improve?

I didn't mean to infer that would suddenly improve my performance. Not being an experienced shooter, I was wondering if my setup was compounding my errors.

If my setup is not an issue, then I'll spend $$ on bullets instead.;)

Since my secondary goal is improving performance/consistency in the field (shooting from improvised front rest), should I bother with rear rest when shooting at the range? (including load development)

Drifter
06-09-2012, 02:25 AM
In no particular order, here are a few things that work for me when accuracy testing from the bench....

First, an accurate AR seems to rely on consistent harmonics. Assuming all aspects of the build are mechanically good, the shooter plays a viable part, perhaps much more so compared to shooting a bolt rifle.

Try "driving" with the offhand up front on the handguard instead of letting it "ride" underneath the buttstock. It seems to control the weapon better, enabling consistent shoulder tension and recoil reaction. (If an AR recoils differently, the POI is usually different.) If using a PRS stock, remove that pesky rail cover and let it get a better bite on the rear bag, which is helpful with the offhand up front.

Don't torque the weapon, where the front hand is pushing right and the trigger hand is pulling left (or vice versa) to get the reticle on target. Trigger hand shouldn't be doing much more than resting on the grip and making a consistent straight-back trigger pull.

Be sure to squeeze the trigger, without knowing exactly when the shot will break. This shouldn't be problematic if the rifle is solid in the bags. If it isn't solid, reposition until it is. Take your time.

Follow through with the shot. Try to see the bullet impact on target. Even if you don't see it, this mental approach can be helpful.

If you're running out of breath, and / or the reticle begins to waiver, back out and start again. Otherwise, the shot will often fly. Stopping a shot is kinda like stopping a golf shot in mid swing. It's not easy, but can be learned.

Try a bubble level on the scope or rail to prevent cant. Cant isn't necessarily bad, unless it's inconsistent (often the case). Five degrees of cant is said to have a half-moa effect on POI.

Find a factory load that the rifle likes. Usually, AA's 123gr Scenar and / or Hornday's 123gr A-max will be good potential candidates. Then, always keep a few onhand as a check gauge, for use on days when shooter or rifle don't seem to be performing up to normal standards. This applies to handloaders as well.

If using handloads, try a small tweak. For example, if you don't crimp, give the Lee FCD a try. If you do crimp, try a load without it. Or try varying bullet seating depth by 5 or 10 thousandths.

Whether using factory or handloaded ammo, realize that some bullets and powders don't play well with others. Or they take several shots for the bore to begin responding favorably. If you shoot 3 to 5 shots of one bullet-powder combo, immediately followed by a different combo, you might never see good consistent groups.

If the barrel has been performing well, but starts shooting poorly with a pet load, clean the barrel. Intervals will vary, but it should be at least 60 or 80 rounds, and could be two or three times that many. Also, a clean barrel might take a few shots to come in.


Disclaimer- I've had no formal training of any kind, and do not claim to be the originator of any of the suggested practices. But I shoot quite a bit, and these basics work for me. YMMV.

ChellieWiles
06-09-2012, 03:03 AM
http://www.google.co.nz/url?sa=t&rct=j&q=rifle%20group%20analysis&source=web&cd=10&ved=0CGAQFjAJ&url=http%3A%2F%2Fappleseedinfo.org%2Fsmf%2Findex.p hp%3Faction%3Ddlattach%3Btopic%3D7814.0%3Battach%3 D10783&ei=hAgOT4CpBISiiAfjz-El&usg=AFQjCNEHq4pi_ifTPXCu3eWCu4vtmwDs6w
that's for a download on what particular shot groupings mean if you have found your zero. I bet you're pushing forward on the pistol grip. Just relax and let the gun push back into you.

BjornF16
06-09-2012, 03:24 AM
LR, Drifter, CW...good words all. I'll work on the mechanics.

BjornF16
06-09-2012, 02:05 PM
Thinking about this again this morning while waking up, I didn't have this problem when I first started shooting rifles (Grendel Entry was my first rifle and AR). I had the Grendel for about a year before I picked up my first bolt action, a R700 in 7mm Rem Mag.

I haven't done any reloading or much shooting since picking up the 7mm due to work until recently, at which time I really noticed the jumping to right. So I think I've developed some bad habits from shooting the 7mm Rem Mag.

In order to break this, do I stick with practicing on Grendel, or do I hit the range with the 7mm and work through the issues there?

Drifter
06-09-2012, 02:10 PM
I suggest working with the milder weapon.

JASmith
06-09-2012, 02:26 PM
I can relate, I once did bench work with a 9 lb .378 Weatherby Magnum. Never could get below about 2 moa. Overcoming the shot anticipation took a huge and protracted effort. That was more than forty years ago (late 1960s) and I still have to work at it!

Go with a .22 rimfire or .223 to be sure you can ignore the recoil. Grendel is the third choice and will work, especially since the recoil is modest and it will build your familiarity and confidence in the rifle and cartridge.

I am also a fan of dry-fire practice. The difference is that today one can get a laser insert to verify that the spot is where you expected. For me, I watch for sight movement at hammer or striker fall and work from there.

Cheers!

ricsmall
06-09-2012, 02:44 PM
The 7 mag will probably compound the problem.take a .22 to the range with you and shoot. Grab a 500 round brick and go shoot it. Don't think too much and try to force shots, the gun will placce the shots if you are mechanically sound yourself. If you're not comfortable with a shot, don't take it. Do what you need to do to relax. Lastly, is your rifle mechanically sound? Above all get comfortable with EACH shot, if that takes five minutes then that's fine. Get your head and mechanics right then the groups will take care of themselves. Lastly again, get a front rest.midway has the Caldwell front rests at decent price, you may find cheaper. If you don't have a solid rest, you're farting in a whirlwind. I'm not an expert, just an experienced shooter thatkeeps it simple. The fewer variables, the better.keep us posted.

davidj
06-09-2012, 09:59 PM
http://www.google.co.nz/url?sa=t&rct=j&q=rifle%20group%20analysis&source=web&cd=10&ved=0CGAQFjAJ&url=http%3A%2F%2Fappleseedinfo.org%2Fsmf%2Findex.p hp%3Faction%3Ddlattach%3Btopic%3D7814.0%3Battach%3 D10783&ei=hAgOT4CpBISiiAfjz-El&usg=AFQjCNEHq4pi_ifTPXCu3eWCu4vtmwDs6w
that's for a download on what particular shot groupings mean if you have found your zero. I bet you're pushing forward on the pistol grip. Just relax and let the gun push back into you.

Good material. Thanks

BjornF16
07-01-2012, 04:54 PM
LOL...

I guess I don't know how to read instructions. :o Both of my LaRue Tactical unimounts were slightly loose. I failed to tighten the bottom screws completely first, before tightening the upper screws. I noticed this morning at the range that there was some "wiggle" in my NF scope. Didn't bother shooting; just brought her home.

Anyone know offhand what torque value I should set the LaRue screws? (Yes, there is thread locker applied to threads).

At about the same time I started shooting my 7mm Rem Mag, I also purchased the LaRue mounts. Killed a lot of brain cells fretting over this...

txgunner00
07-01-2012, 05:31 PM
12-15 INCH/lbs is pretty typical for aluminum rings and mounts. 20 in/lbs for steel. It's much less that most people think it is. I'll bet 99% of scope rings in the world are over torqued.

BjornF16
07-01-2012, 05:56 PM
"Bing'ed" it..http://www.opticstalk.com/torque-specs_topic18389.html

30-35 in/lbs according to LaRue Tactical tech support.

http://www.youtube.com/watch?v=rgmmdDp0VDA&feature=player_embedded

stokesrj
07-01-2012, 06:22 PM
I think your skill for your level of development is normal. It takes a lot of rounds to learn to shoot well. It is the basics that count but they can be very hard to master, it is mental not physical that gives you the most problems. I would say that the issue is not your set up, but your understanding of how to use it properly. (assuming you have tightened down your scope rings and still want to improve)

The basics are sight alignment, sight picture, trigger control, and follow through.

By sight alignment I mean that your head is placed on the stock with your cheek firmly in contact and positioned so that your head is vertical and your eye aligned with the center of your scope or sights. Ideally the stock should bear the full weight of your head so that your neck muscles are completely relaxed, there should be no effort whatsoever to keep your eye in alignment.

By sight picture I mean that after you have achieved alignment the sights are centered on the target, if not, move the rests until they are, do not muscle the gun to the target, move the rests. If you are bag sqeezing it should be minimal and by minimal I mean it should move the sights by no more than 1/4 moa and it would be better to not move it at all.

By trigger control I mean moving the trigger straight back without upsetting the sight picture. Dryfire to check this at least a dozen times to check that your sights are not moving, and if they are work to find out why and eliminate the movement. You can't shoot good groups unless you can do this and it would be a good idea to check maintenance by firing live rounds and dryfire alternately as you shoot your groups. You will find that a medium firm grip on the pistol grip similar to a firm handshake will yield best results. It isn't important where your finger contacts the trigger as long as it moved the trigger straight back with no side to side force. You should not use the pistol grip to move the rifle for sight picture, this is death to peak accuracy, again, move the rest.

Follow through requires that you keep your eyes open through the shot and recoil. You should be able to call your shots and you will as you develop this skill but it will take a while. For my junior rifle team I require that they plot each shot before looking through their spotting scope and compare the plot with the actual impact point. This is very valuable training and results with them being able to call their shots within 1" at 200 yard in the offhand position.

If you have mastered these fundamentals you have probably fired more than 2,000 rounds in quality practice sessions. Most require 10,000 or more.

Bob

BjornF16
07-01-2012, 06:46 PM
Bob,
That is the most informative online coaching I've rec'd...thanks!

I realize that there is no single "golden bullet" to my mechanics. The scope setup appears to be a significant issue. This morning the scope was moving approx 10" across target (at 100 yds, so 10 MOA) when I physically moved it left/right. I have spent the last couple of hours setting up the scope and rings properly, including using levels. One level on top of picatinny rail, the other on top of 12 o'clock knob.

I've never tried "truing" the targets to vertical...do y'all use a plumb bob to align targets?

I have been "muscling" the rifle to the target...I noticed this on my last session. I would remove my trigger hand completely from rifle and the sight would move several inches to the right of aim point. I need to spend more time in "setup" before pulling the trigger the first time.

I know that occasionally dry firing with pistol can reveal a "flinch" trying to oppose the muzzle flip. I suspect dry firing with rifle will reveal some similar reaction.

Question: How many rounds do you recommend sending down range for a single, quality shooting session?

Many thanks again!

stokesrj
07-01-2012, 07:19 PM
I shoot with some of the nations top shooters, I don't claim to be one of them, they have many national records among them so I listen to what they say. Most of them dry fire many times the number of live rounds fired each year so that is some valuable information that most casual riflemen will never hear and if they did would not heed.

Most training sessions I hold with the state junior high power rifle team consists of 88 shots which is a standard regional match course of fire. 80 shots for record and 2 sighters for each stage. That is somewhat of an endurance test. So unless you are training for a match that requires endurance, I would limit to maybe 50 rounds. And those 50 shots should have a specific objective and have dryfire exercises incorporated.
I wouldn't worry about load development until you have the fundamentals mastered. Just pick a good load and stick with it.
Bob

stokesrj
07-01-2012, 07:23 PM
By the way, I'm 58 years old and have fired tens of thousands of rounds in registered high power competitions, and I'm still learning. In fact next saturday I'll be training for the National Infantry Team Trophy match and my trainer is in his 60's. Learning to shoot a rifle well is a life long endeavor.
Bob

LRRPF52
07-01-2012, 07:57 PM
By the way, I'm 58 years old and have fired tens of thousands of rounds in registered high power competitions, and I'm still learning. In fact next saturday I'll be training for the National Infantry Team Trophy match and my trainer is in his 60's. Learning to shoot a rifle well is a life long endeavor.
Bob

Amen to that...

I read The Red Circle, by Brand Webb on the plane ride across the Pacific, and I was most impressed by what he was involved in with totally re-building the Naval Special Warfare Center Sniper Training program. They incorpotated a lot of unorthodox techniques, principles, and approaches to shooting, memory training, mental management, and instructor-student relationships to totally create a new regimen for making better SEAL Snipers, and the results paid off with measurable results.

They went to guys like Lanny Bassham, who wrote With Winning in Mind, and studied what an olympic shooter thinks, and how they think. They assigned student sniper pairs to instructors, and had all the instructors competing with each other to get their teams shooting better than the others, rather than the old, disconnected, "value attrition like it's a thing of pride" traditions where the blocks if instruction were given, and they could care less if you learned and demonstrated gaining new skill sets.

They started cranking out dudes who could shoot better than ever before, with much higher course standards, and more difficult training objectives. It was a totally "outside the box" approach to instruction, especially from within a military setting.

It sends home the statement about shooting being such a mental activity, and how mental focus and attitude play such a huge role in being a good shooter. I highly recommend the book, even though I look towards the Squeals from a perspective of rivalry.

stokesrj
07-01-2012, 08:49 PM
I have read "With Winning in Mind" and have Larry's CD's as well. Good information.
Bob

BjornF16
07-01-2012, 10:24 PM
After lunch went to shoot my last 40 115 Bergers from AA. Went much better after adjusting scope. I went ahead and put my Harris bipod back on. Interestingly, the first shot after reloading always hit high. Not sure if there is something odd going on with bipod (bouncing, "loaded" differently after first shot?).

Shoot 4, dry fire 4. Repeat. Seems to help. Need lots more range time. The dry firing helps more than I would have thought. Ultimately saw very little movement in scope at trigger release. Results posted below: Group of 5 near end of 100 yd session; 100 yd session; 200 yd session (complete with rain storm between groups of 4).

JASmith
07-01-2012, 11:12 PM
Don't stop!

Those groups say that a squirrel is in deep doo-doo at the 200 yard mark. Also, mouse at 75-100 yards would be at risk if you could see him first! :) :)

Variable
07-02-2012, 01:53 AM
LOL...

I guess I don't know how to read instructions. :o Both of my LaRue Tactical unimounts were slightly loose. I failed to tighten the bottom screws completely first, before tightening the upper screws. I noticed this morning at the range that there was some "wiggle" in my NF scope. Didn't bother shooting; just brought her home.

You aren't the only one!LOL I put them on right for a while, and then I hadn't mounted any for a spell and brain farted when I mounted up my 2.5-10x NF. Same exact thing. Scope wiggle = "WTH???".... "Awww crap!" I felt so stupid I neglected to mention it for a while.;) I'm just glad it was one that went on one of my guns and not someone else's. I'd have never lived it down if I had done that one on somebody else's setup!!!:o

LRRPF52
07-02-2012, 08:47 AM
Always read the distractions...I mean destructions....I mean instructions.

Nice groups BjornF16. Yes, dry-firing is a common practice among competitive shooters as stokesrj pointed out, accounting for more trigger time than actual live fire, even with some range sessions exceeding a thousand rounds for action shooters.

ChellieWiles
07-02-2012, 06:13 PM
my technique when shooting is to put the crosshairs on where I want to hit and pull the trigger at that time. it has worked well for me with every gun I have ever used.

BjornF16
07-07-2012, 05:17 PM
Drifter - thanks for your inputs. I put some of your and Bob's suggestions to work today.

Shot 5 groups of 5, with the first 4 groups at 100 yards and the last group at 200. All off of a Harris bipod on a concrete bench, but adjusting POA by sitting position (i.e. no sandbags at all).

Group 1 was more of what I had been doing with exception of putting my left hand on the handguard. Still used a light/loose grip. My rifle apparently doesn't like loose holds!

Groups 2 - 5 were same basic position but holding the rifle much firmer into shoulder with left hand. With the exception of group 4, I took my time between shots (closing eyes for a 10 count, then re-opening to check aim). Group 4 I didn't bother closing eyes and had a much quicker shot cadence (with corresponding opening of group).

Drifter
07-07-2012, 05:45 PM
All off of a Harris bipod on a concrete bench, but adjusting POA by sitting position (i.e. no sandbags at all).


FWIW, when chasing for the best possible groups, a bipod on concrete wouldn't be my preferred method. It potentially makes the rifle more temperamental, requiring a firmer hold to maximize results. A bipod will tend to bounce on a hard surface, and it can be difficult to load the bipod in the exact same manner each time. POI shifts compared to other methods and / or from more forgiving surfaces are not uncommon.

That being said, one should test a weapon in the same application as its intended use, or in the manner that the shooter prefers. But sandbags front and rear from the bench would likely provide the best opportunity for tiny groups, and works best for me for load evaluation.

BjornF16
07-07-2012, 05:56 PM
Thanks Drifter. I'll remove the bipod next time and try off the sandbags. I haven't done that since tightening down the scope.

Rambozo
08-10-2012, 03:24 PM
I was going to suggest looking at the scope mount, though it seems you worked that out. Also be sure not to straddle the mount between the receiver and the handguard rail. That too can give horizontal stringing.

Your groups look more consistent now, which suggests to me that it was the mount.

jessegibson1978
11-27-2012, 01:09 PM
Anticipating the shot is a very bad habit it will cause you to jerk or slap at the trigger usually causing the shot to go right and usually up for a right hand shooter. It's like shooting a bow if it doesn't surprise the crap out of you then you probably slapped the trigger. Just think squeeze the trigger. Have some one load a bolt gun for you fire some and have them at one point unknown to you hand you the rifle with an empty chamber you might be surprised by what is happening. If it's what I suspect it is you will immediately see the cause. Good luck and good shooting.

JASmith
11-27-2012, 01:23 PM
Jesse,

Excellent advice!

jessegibson1978
11-27-2012, 01:27 PM
Woops should have read whole thread first but may help someone else.