OAL tell me the truth

[Rabbit]

So... I would rate myself a 3 on a 5 point scale when it comes to skill and knowledge on reloading. Let's say, I haven't done anything to hurt myself or anyone else as yet. I load pistol .40, .45LC, .45ACP, 30-30, .308 Win, .300 Blk, 5.56.

When it comes to overall length consistency, for the life of me, I cannot routinely produce repeatable results at the exact overal length. Especially with these ballistic tip SST's

I trim my brass to the same tolerances. Set my seating die to produce a COL of 2.255 and I end up with rounds that vary (mostly on the short side)by 1 or 2 thousands.

I have a single stage rockchucker press with Hornady dies and a Lee factory crimp die.

Is this me or how on earth do I achieve repeatable results?

I am interested in hearing and improving my skills.

[JASmith]

I have had similar experiences too.

The variations largely result from minor differences in the ogives and tips but the actual jump is more consistent than the base COAL suggests.

Using a comparator like the Hornady OAL gage shows more consistent results (http://www.hornady.com/store/OAL-Gauges/).

The gage comes closer to catching the actual variation in jump than the COAL implies.

Interestingly, the gage contacts the bullet between the typical contact point for seating stems and where the ogive actually engages the rifling.

[rabiddawg]

I agree with JASmith.

Measure just the projectile and you will see that difference.

Now you can move up to a 4!

[Kikn]

JA is spot on ::thumbs up::

[Redomen]

I have also noticed this issue. I reload the NBT 130gn for my .270 bolt rifle. I am usually pretty close on OAL but it still bothers me and my OCD. However I have not had any complaints from the deer or hogs to date.

[FW Conch]

Yes, "JA" is right on, as He usually is. The differences in pills is considerable. Case Base to Ogive is what matters for accuracy. Cartridge Over All Length is only critical to magazine function. The solution is to measure and sort Your pills before loading them. Midway sells a tool that looks like a nut with 6 different size holes in the sides to measure Bullit Base To Ogive. Or You can make Your own comparetors out of tubing.

When Your finished sorting by length, then You can sort those categories by weight!

My BIL has 5 categories for each pill! Now that's OCD! ;-))

[diddlyv]

When I started reloading it was for NRA hi power matches and I was using 168 smk bullets. Overall lenght was driving me crazy, in desperation I called Sierra. They told me the bullet tips varied a lot but not to worry about the minor differences as it was a function of the very tip and not the ogive.

[Rickc]

I have done the bullet sorting routine. Don't see any real advantage to it for me. If you are a long range competitor you might see a slight difference but there are lots of other things to do first.

I feel like if you have a good seater and they all are seated consistently then I am good to go. If you do the bullet seating thing you will find the bearing surface longer on some bullets. you are really sorting by bearing surface. With premium match bullets 80% will be very close to the same.

http://www.sinclairintl.com/reloading-equipment/measuring-tools/bullet-comparator-inserts/sinclair-bullet-sorting-stand-prod38769.aspx

[Rabbit]

Thank you Hord. Glad it's not just me. Next step up needs to be a comparator I guess.

[diddlyv]

Took me 22 years but am now a member of the enlightened reloaders who use the comparator and in my case the head space bushing to set the sizing die to knock the shoulder back just .001 or .002.

[Rabbit]

I spent quite a bit of time last week putting lead to paper..without a comparator as yet. The last 25 rounds sorted into groups based on OAL with seater set up for 2.250 on the first round just to see how much group variation I might have. Honestly, I didn't notice all that much variation in my groups.. @ 100 yards. Groups were 1.5 to 3" with a few called fliers. More operator error than COL I believe. Just to say it..my range set up is primitive, kneeling and braced on a tree stump. Funny how one notices the subtle movement of the weapon on each heart beat..when your trying to one hole the paper. After doing a little more reading, I get the consistency of the comparator, it removes one more variable from the equation....Thanks again.

[JASmith]

...my range set up is primitive, kneeling and braced on a tree stump. Funny how one notices the subtle movement of the weapon on each heart beat..when your trying to one hole the paper...

You are doing very well with that form of rest, but there's an awful lot of evidence to suggest that there's a wide variety of ammunition that will do as well.

Why? One needs a solid rest to eliminate as much of the human factor as possible from the accuracy equation. Once one is sure the ammo does better than the hold, then go back and practice what appears to be an opportunistic field position.

For me, its a good Caldwell front bag and a rear bag on a bench. I know I don't use what many would call good technique, but going from a purpose built hard rubber support to the bags and a good optic let me get to where I do get the occasional sub 0.5 moa group.

Your groups tell me that the advice some folks on this forum can give will allow you to get routine 1/5-moa class groups or better.

[Fredman]

I think everyone is wrong.

You need to buy a new press, Dillon? A large variety of bullets, pounds of powder you have been wanting to try, new rifle and maybe a NF scope. Try all that and see what you have. I know I'd be smiling...

[JASmith]

I think everyone is wrong.

You need to but a new press, Dillon? A large variety of bullets, pounds of powder you have been wanting to try, new rifle and maybe a NF scope. Try all that and see what you have. I know I'd be smiling...

That's what happens to many of us...and one gets sucked into that quagmire more quickly when one gets comfortable with how he and his rifle shoot. I will admit, however, that they kind of happen together.