Home Forums Hunting & Shooting Ask The Gunwriters Two out of three and OAL

I have a beloved rifle that has the nasty habit of putting 2 shots next to each other and a third shot "flyer"

I recall reading a recommendation here on the 'fire some time ago something like the following:


"start by looking at the shape of your groups. If there are 2 together and the 3rd shot out of the group, the OAL is too long for your rifle chamber and you need to seat the bullet deeper."

is this a generally accepted protocol?

Playing with seating depth can often help, but I haven't found that technique to be always consistent--partly because 3-shot groups aren't always a good indicator--especially if you're not using wind flags.

It could also be due to other reasons, including the barrel not being stress-relieved, or action/barrel bedding. I am sure others will be along soon to list every possibility....

You don't offer any other factors such as the barrel contour - is it a lightweight, thin barrel. If so it may be a matter of change in harmonics due to heat effects on the barrel. In that case there's the only solution I can think of is dampening - as opposed to floating - the barrel. In other words, a full-length barrel and action bed. Not saying that's the situation here of is so, the only solution. Just something for you to consider and explore.

Thin barrels aren't any more affected by heat "harmonics" than medium-weight barrels if they're properly stress-relieved and bedded. Melvin Forbes repeatedly proved that for decades with Douglas barrels in his Ultra Light and New Ultra Light Arms rifles--but yes, he "dampened" them by full-length bedding them in his very stiff synthetic stocks.

Thanks for the replies. FWIW, the rifle is a M70 FWT, Shot Show Special in 280Rem

Make sure you clean all the copper fouling out of it. Some were copper mines. Then shoot 5 shot groups when diagnosing group dispersion. That’s a minimum, but will definitely show what some of us refer to as “double grouping”. 2 in 3 out for an example. Often times shortening OAL will help. As does adjusting powder charge. However, if you are at the group diagnosis stage, you should be at OCW. Then fine tune with OAL, or even switching to a better performing powder, will help. This is assuming your rifle is solid mechanically, you are shooting off a good rest, and you are doing your part.

Thanks, appreciate the input. I'll check the copper. Rifle is in good shape and has had the "Redneck treatment". I could be the culprit, but the "2&1" happens so regularly with this rifle and not so much with others. And I have tried multiple powders and OALs.

This may help: https://bergerbullets.com/getting-the-best-precision-and-accuracy-from-vld-bullets-in-your-rifle/


Okie John

How far off is the 3rd shot?

What do 5-shot groups look like?

If it’s repeatable and does it over and over I’ll start shortening my OAL. Some bullets will respond to shortening and some just don’t care as much. A couple 3 shot groups usually shows me the trend.

Wouldn't hurt to check concentricity also. A lot of my flyers started going away once I started measuring that and correcting. I'll always have a couple out of a batch of 20 that are a little off no matter how smooth my reloading is going. I even check factory ammo with it.

How is it stocked? Wood, composit? Maybe a beding block? Check beding for shiny spots, indicating a high spot or action flexing. Check the bottom of the lug recess if a block, might be binding, BTDT. Beding is the first thing I look at, if not perfect, you`ll pull your hair out, and waste a ton of ammo and time.

Good Luck

On any Model 70 tossing shots, the center action screw is the first thing to look at.

Good shootin':) -Al

Yep--and often the simplest solution, which is where anybody should start with any mechanical problem.

Same deal with the front screw on the trigger guard in Remington 700 ADLs....

Has anyone offered a plausible explanation for how seating depth or COL would lead to a consistent 2 in 1 out? Has always sounded like pure bullchit to me. About as dumb as choosing a load based upon a single trifecta.

Yeah, if seating depth was leading to one being out of the group, why wouldn't they all be out of the group so to speak?

That's one of the "problems" with 3-shot groups. If two shots are closer together (and that's the odds when shooting 3 rounds), then the third is often called a "flier."

In fact I have good friend who shoots 3-shot groups until one ends up in a nearly perfect, small triangle--then shows that group off, which to him proves that's THE LOAD.

Jim Carmichel wrote about this decades ago, saying that most "pet loads" are the result of one 3-shot group....

By that reasoning though, anything that causes 2 and 1 should have them all out of group.

I often only shoot three shot groups but I shoot a lot of them before making any declarations. I have saw the two and one thought debunked by a few 5 shot groups showing it just to be part of the "pattern". I have also saw OAL affect group size as I imagine most everyone here has. I always start at either a kiss or at the max OAL the mag box length will allow. That way there is only one direction to go if there is a suspected problem.

It's a bit of brute force, but one way to know the outer limits of what's going on with grouping is to keep shooting until the hole in the target stops growing. I've done that a few times with a couple of my heavier 308s.

My fellow gun writer John Haviland did that with a New Ultra Light Arms 7mm-08 he'd requested Melvin to send for an article. John has heard (perhaps from me) that you could NULAs really hot and they'd maintain accuracy and point-of-impact--so after shooting one group small normal-number group he just kept shooting. If I recall correctly, he put 20 rounds into less than an inch before quitting. (Which is when he decided to buy the rifle....)