2 touching, 1 out

[frankm]

Working with new 300 WM and 180 grain AB s. R22 is powder I m using. Issue... Have shot bullets anywhere from .030 to .100 off the lands and getting 2 touching with third round (3 shot groups) going an inch or inch and a quarter away.. Should I continue shortening my cartridges ten thousandths and can I expect to see groups tighten at some point? I ve used from 73 to 75.5 grains of R22. Velocities from 2900 to 2975 depending on charge. Fed 215 and CCI 250 s both tried... No difference in grouping.

Just to clarify that scope, bedding, etc are OK I ve shot 165 AB with 79 grs of R22 and consistently under MOA with best of .375!

Appreciate hearing everyone's thoughts!thx

 

[SJB358]

I'd keep shortening in smaller incremenents. Eventually you will get to the point where you can't go any further or you'll pull that 3rd shot in.

 

[HeathSexton]

I've had good luck shortening the rounds .005" at a time.

 

[Elkman]

I have found with the AB's that the "exact" that your rifle desires may be hard to find, as Heath/Scotty says shorten up the increments, and see if that works. Mine likes the factory recommended AOL, plus 10, they barely fit in the magazine.

 

[Silent Sam]

Always the third round out? What happens if you shoot five?

 

[frankm]

SS, good question on which one out... It's random... Regarding 5 shot group I ve wondered about that myself, haven't put additional rounds in group as barrel gets hot and would have to wait thus creating another shooting variable.

Think I ll continue with shortening cartridge length but in smaller increments as mentioned. Keep any other ideas coming! Thx guys.

 

[Silent Sam]

Make a composite target and look at the group center and group size of first shots.

 

[kraky1]

Shoot further than 100 yds...see if the groups open much more. 200 yds is the minimum for final testing for me. I've seen mediocre groups at 100 perform pretty nicely at 300.....I've seen decent groups at 100 perform crappy at 300. Alot of that has to do with bullet stabilization.

 

[frankm]

Good input, more things to work with. Thx guys!

 

[TXbaldhunter]

I've been working on a few rifles with the same problem recently.If seating and load adjustments don't work,there is another option that might fix it before you give up.About 5-10 of the David Tubb Throat Maintenance Bullets did the trick.I've used both kits before and every rifle has shot much better after using them.See the video: https://www.youtube.com/watch?v=SIvvTxVnx_g

 

[frankm]

Thx for Tubbs tip. I already did that prior to load development. Every non custom barrel I have gets the same. In my experience helps accuracy and more important truces copper fouling and cleaning time !

 

[ElmerThud]

It's an interesting problem - 2 touch, 1 out.
A friend and I both experience a similar issue with different cal. rifles.

We found allowing the barrel to cool off properly (patience required & unhelpful if shooting in warm temps.) between shots brought the group in nicely; and, this could be extended over a few rounds.
Then, there are other interfering issues to deal with.

Either way, if you're hunting, the first shot cold & clean should bring ol' beastie down....if playing with paper at long range, plainly it matters more.
Good luck with resolving the issue.

 

[baltz526]

Try shooting three 2 shot groups. Let the barrel cool completely between each. If you still have fliers it might be parallax in your scope.

 

[Firebird]

Just curious what you coal is? I shoot 180 ab in .300 wm as well and was surprised how deeply I had to seat them to get consistently appreciable groups. I don't have my own load info handy and it would be different for every rifle but seating depth was the key for me and it had to be deeper than I expected-

 

[frankm]

FB ,

Tried from .030 to .100 jump ( 3.560 to 3.490 OAL in .010 increments). I know I m still .100 long from SAMI but haven't tried anything shorter than 3.490. Other than Weatherbys I ve typically always found accuracy longer than SAMI. How much jump did you end up needing for your accuracy??

 

[Gunner46]

I've come to the same conclusion as Blatz when I'm working on a 'final' hunt load. Where does the 1st round hit (#1 concern), and then where does round two go without extended cool down. That is what you'll face in the field.

In over 40yrs of hunting I've only had one 3rd shot, and that was because I made a marginal hit on the first one and hurried the second.