what is a GOOD group for Grendel?

[Former Cav]

With NO B.S (please).
1) shooting from a bench rest in a comfortable position with sand bags or a "sled"
2) shooting at 100 yards from the above position
3) 5 round groups (not THREE round groups)
4) with an AR-15 rifle
5) either hand loads or factory.
I have posted elsewhere and my BEST load is 13/16 inch with VARGET but the bullets are moving at 2300-2350 FPS. All the other powders would NOT give me 1 inch (1 MOA). The factory Hornady 123 SST and the other 123 they have on rounds 1, 2, 3, they are good, then rounds 4 and 5 open the group up to TWO inches. Also the same results with an National Match (Camp Perry type) shooter.

SO, what are your results.

[LR1955]

With NO B.S (please).
1) shooting from a bench rest in a comfortable position with sand bags or a "sled"
2) shooting at 100 yards from the above position
3) 5 round groups (not THREE round groups)
4) with an AR-15 rifle
5) either hand loads or factory.
I have posted elsewhere and my BEST load is 13/16 inch with VARGET but the bullets are moving at 2300-2350 FPS. All the other powders would NOT give me 1 inch (1 MOA). The factory Hornady 123 SST and the other 123 they have on rounds 1, 2, 3, they are good, then rounds 4 and 5 open the group up to TWO inches. Also the same results with an National Match (Camp Perry type) shooter.

SO, what are your results.

FC:

Hasn't changed for decades. You should expect 3/4 to a minute given a decent barrel and match grade bullets providing you want it.

Easier to get with a tangent ogive than secant (standard vs low drag).

Normally easier to get with light and medium vs heavy loads.

Factory loads may be more dependent on the quality of the barrel than handloads.

'National Match Shooter' may mean the guy is a Marksman. If the guy is a Master or High Master, I give him or her more credence than a Expert or Marksman.

Optic or dot sight will probably be better than irons. If irons, aperture sights (Match Rifle) will be better than Service Rifle sights given a round black bullseye on a white target. If optic, lower magnification better than high. If choice between zero magnification dot and optic at 100, you may find a two minute dot to give better and more consistent results than a magnified optic.

A bench set up that fits you and ensures you have a firm and confident hold on the rifle -- which is also pointed into your target without much effort -- is better than a uncomfortable and unstable position. Obviously, shooting off a flimsy card table will not give performance like a solid concrete bench made for rest shooting. Shooting with an unnatural position will not be as consistent as a natural position.

Shooting faster is probably better for accuracy than slow fire. Looking through a scope at the hole between shots (with the time taken) is rarely successful. Get the position and shoot the string. Call your shots and you will know if you shot a decent group. Study the group after the shots. Five shots ought to take about three or four seconds once you are in your position and are confident your position and you are ready.

Train your eyes to see what 'good enough' is for your purposes and have some confidence that what you are seeing is either good enough or not good enough.

I am a big one on calling shots. To me, if a shooter can't call his shots well enough to meet his standards, he may never achieve his shooting goals. In your case, train your eyes to see what 3/4 inch is at 100 yards and if your shot goes there, you should know it without having to look. If it doesn't go there, you should know where it went (within reason) without having to look.

It is not unreasonable to expect about 3/4 minute from a decent barrel and decent ammo.

LR-55

[Zeneffect]

On a scale of 1-10 where does good sit? Is "sub moa" good these days or has that standard risen to 3/4 or 1/2?

3/4" is good, it's not great or excellent... or maybe its excellent and 1" is good. Perception and requirements make the answer a real unknown.

with a well developed load, .3" smaller is not uncommon.

[LR1955]

I thought 'sub minute' meant below one minute. Like 3/4 or half minute maybe?

3/4 minute mean for group after group is pretty good given a decent rifle, sighting system, ammo, and shooter.

Next question ought to be 'at what distance'? Accuracy isn't linear in my opinion, and I would be pretty happy with a load I could pull out any day of the week and know it can hold 3/4 minute at the distances I want from it -- 300 to 700 yards in my case.

If FC wants something he can depend on to shoot half minute, on demand, group after group, at distance, he will end up having to spend a fortune and make precision marksmanship his life. That's not what he was asking, but rather what can he expect from decent gear and ammo.

LR-55

[LRRPF52]

For me, it has always been about the quality of the barrel, tight assembly of the barrel (bedded or thermo-fit) and the consistency of the load, assuming a very consistent shooter who knows how to run a gas gun in a larger cartridge than .223 Rem.

With .223 Rem and its tiny projectiles, you can free-recoil the gun and shoot great groups much of the time.

I have not found that to be the case with 6.5 Grendel AR-15s. I drive them like I do an AR-10.

Here are some groups though:

123gr ELD-M, 12” group buy Faxon low price/economy barrel:



123gr Hornady American Gunner, 18” LaRue Stealth 2.0:



94gr Hornady GMX cut down from 120gr hand load, 17.6” Lilja:



90gr Federal TNT factory ammo, 12” Faxon Grendel again:

[LRRPF52]

From way back, my 16” AA non-bedded barrel at 200yds with 123gr A-MAX factory ammo:


Also from my original 16” Grendel:




1000yds, 17.6” Lilja Grendel, rapid-fire, 6rds, 123gr A-MAX on 31.2gr CFE223, Lapua brass (8” vertical, 4” horizontal):



22” Lilja bull fluted, 5rds rapid-fired 123gr A-MAX I think:

[LRRPF52]

More 22” Lilja bull barrel, rapid fired 100yds:



Lilja 17.6”, can’t remember the load:


The best-shooting Grendel barrel I think I’ve ever tested, a 20” Bartlein from Precision Firearms:

[Former Cav]

The NRA highpower shooter I was referring to is a HIGH Master and distinguished! I used to do the OTC (200,300, 600) and Palma (800, 900, and 1000 ) before my health went to he11. I was shooting an AR over the course, and sometimes my M1A, and a custom built bolt gun in 308 at Palma. All were with Iron sights. I got as high as the bottom end of Expert (89 percent and on a GOOD day I'd be hitting on the edge of 92).
With my Prairie dog rifles they all shoot at 1/2 MOA. when they get to 3/4 inch the barrel gets replaced (I tried the set back and recut the chamber and it wasn't worth the expense and results).
If you have a 1 inch prairie dog rifle and the adult prairie dog is 4 inches wide and is 500 yards away, you MISSED!.
I wanted this rifle to be at least close to a 1/2 inch. I've posted the 30 or so different ladder loads on here and some folks asked if I knew what I was doing.

[Zeneffect]

So you were shooting this grendel with irons? Nothing wrong with that just asking.

"For me, it has always been about the quality of the barrel, tight assembly of the barrel (bedded or thermo-fit) and the consistency of the load, assuming a very consistent shooter who knows how to run a gas gun in a larger cartridge than .223 Rem."

^ THIS.

Barrel + bolt + fit to upper + quality of trigger + how well you can shoot and work your optic or sights.

[Klem]

Cav,

Best I can get is 0.8MOA on average.

Data is attached and has been posted previously. It was testing crimping vs.neck tension.

Using a match grade Lilja 319, 7075 receiver, SPUHR mount, March scope, and Geissele NM trigger. Shot over several range sessions.

Maybe you could shrink that to 0.75MOA with a newer barrel and more careful selection of bullets. This result is from shooting 78x4rd groups using the 120NBT and your criteria. I get better results with heavier barreled bolt guns using 3" wide stocks, which highlights the inherent handicaps of the AR: light weight, flexible receivers and stocks, semi-auto, thinner barrels, thin rounded handguards moving in the recoil.

I'm with 55 and 52 on this, you need a match grade barrel to shoot sub MOA on average, plus a good scope and trigger. You have to hold it more and be consistent in how it's held.

[Former Cav]

Thank you Klem.
If I get the chance to get away, I'm going over to a store that claims they got TAC ramshot rifle powder in stock. I saw Dianne's Post and I'll have to give that a try.
OH, and here is one for LAUGHS.... I tried a kit that "FIRE LAPS" the barrel on the first upper I had (which the barrel is scrapped out). Ha ha, it went from 2 inches to about 8 inches!!
I guess I won't be trying FIRE LAPPING anymore!
This is the FIRST Caliber I have ever had so many troubles with in getting a group. Between my wifes (and mine) health issues, then moving to TX fro AZ, and trying to buy powder, bullets, etc it has been a very difficult time.
With both .223/5.56 and .308/7.62 all I had to do was ASK (and this was after I did the ladder load process) and the NRA match shooters said for 223, 77 grain Sierra Match Kings, 24.5 grains of Varget, Standard small rifle winchester brand primers and LC brass or NEW winchester brass and it is right on. Likewise for the 7.62 Nato. I had a load worked that was 44.4 grains of win 748, std lg rifle primers, 150 grain BTSP hornady bullets and LC brass. (I also used R/P nickel brass as it was easier to find in the grass). The shooter says to me. 175 Sierra match King, 45 grains of varget, your standard win primer, and LC brass. FIRST shot at 1000 yards and I was on the edge of the 10 ring at 3 oclock. So I asked the shooter, hey, I have 500 155 grain palma match bullets what should I do for them. He says "same load". I said okay, then the trajectory will be different, he says, well at 300 meter international match I drop 1 MOA and the guy was RIGHT ON.
I miss those guys.
I worked up loaads for the .243, 25-06, 6.5 x 284, 7.62 and 5.56 and NEVER had this many problems.
I'm about ready to give up and convert to a 260 Remington. Of course, that will cost another couple of grand by the time I'd get done with it. (that's the only thing stopping me)

[Klem]

Cav,

Your expectations of 0.5MOA are with respect, unreasonable in an AR. A few groups in every session will be 0.5, but the average is going to be wider, and that goes for all calibres. Even with the best of everything an AR is still not as accurate as a decent bolt gun.

Those 78 groups came from 120NBT, 27.7 gns H4895, at 58mmOAL using Lapua cases and CCI450 primers. Your Varget is a bit slow for typical AR barrel lengths. Unburnt powder out the end is going to mess with your group size. As will compressing the load while trying to improve the velocity.

Grendel has the smallest boiler room of the 6.5 calibres. It lends itself to lighter 6.5 bullets and out of an AR15. If as you say you are thinking of moving to a 260Rem then you will find the same amount of bullets available in the shops and online. Supply of powder and bullets is slowly returning.

It sounds like you've had a bad experience with a dud barrel, along with unreasonable expectations and not a lot of time/patience. It's up to you but you will be throwing the baby out with the bathwater, moving on to the next disappointment. Any barrel that needs lapping is going to be hard work to shoot well. Buy once cry once; get a match-grade best-barrel. In an AR the difference is only a couple of hundred dollars. The opportunity cost is that you spend that money in ammo, trying to get a cheap tomato stake to shoot.

[LR1955]

The NRA highpower shooter I was referring to is a HIGH Master and distinguished! I used to do the OTC (200,300, 600) and Palma (800, 900, and 1000 ) before my health went to he11. I was shooting an AR over the course, and sometimes my M1A, and a custom built bolt gun in 308 at Palma. All were with Iron sights. I got as high as the bottom end of Expert (89 percent and on a GOOD day I'd be hitting on the edge of 92).
With my Prairie dog rifles they all shoot at 1/2 MOA. when they get to 3/4 inch the barrel gets replaced (I tried the set back and recut the chamber and it wasn't worth the expense and results).
If you have a 1 inch prairie dog rifle and the adult prairie dog is 4 inches wide and is 500 yards away, you MISSED!.
I wanted this rifle to be at least close to a 1/2 inch. I've posted the 30 or so different ladder loads on here and some folks asked if I knew what I was doing.

FCG:

No offense but the way you worded your original post implied to me that you were new to the game. I have read dozens of similar posts and all were from shooters who lacked experience. To me, a experienced shooter wouldn't need to ask what you asked. An experienced shooter would know what to expect from what are basically rack grade components and would know how much of a problem was due to him and how much due to his gear.

Also, a lot of guys new to the Grendel think it is something magic that will shoot half minute by itself. Maybe by itself it will but probably not with someone shooting it. Given the hype over the Grendel, I can understand the frustration when a shooter is faced with reality. It is a pretty easy cartridge to get to shoot about 3/4 minute. Under that and I see the luck factor becoming more probable.


LR-55

[LRRPF52]

Hornady published an interesting YouTube video about this basically saying that if your group sizes are averaging really small, you aren’t shooting enough.

Ammunition variables even through super-accurate rifles will always open the mean POI from POA until it’s over 1 MOA if you shoot enough.

The only rifles I have seen that shoot consistently in the 1/2 MOA region are benchrest rifles with tight chambers that don’t even require re-sizing of the brass after each shot, and can be loaded right there on the range and fired repeatedly. That won’t work for a gas gun.

[DHD]

I can't say how it will work for you for me a load that has shot well for me in every barrel I have had in the Grendel. I have or had AA 24" Overwatch (my first barrel in Grendel), Satern 24" cut rifled, Proof Research 20", Proof Research 18", and a Rainier Ultra Match 16" (Criterion chambered by Craddock I understand).

AA brass (Lapua) annealed every time
450's (Wolf SRM are great too but....)
31.2 LeverRevolution
120 SMK (mine are all pointed)
.025" off of jam (each barrel is/was slightly different)
This load has been used by me to 600 yards and it was great there too. I full length size without the expander and use a 21st Century mandrel die w/.2615" mandrel.

This is a stout load but has been safe in all of my rifles. My brass will go beyond 7 firings and not lose a primer pocket. The 120 SMK is not a sexy bullet as far as BC is concerned but it tunes easliy. A Berger 120 BT is even better for easy accuracy but are not existent and I was not smart enough to buy a pile some years back.

I just built a 16" Grendel (Rainier Ultra Match) and it appreciates this load too but it's not surprising to me. As usually mentioned, back off a touch and work back somewhere near there if your rifle allows it. I can't say how Starline will hold up to this load.

I usually shoot my Grendel AR's off of a Randolph front rest and either a Protektr or Edgewood rear bag. So typically I treat them similar to a Benchrest rifle. That said, I "hold" them. When I ease up and start to not hold them, groups open up.