Help !

[veeramani]

I've got an RRA 20" AR10 heavy barrel. (0.936 inch).

Got some 167 gn scenar handloads and it keyholes at 100m, 300m is geat too.

When I take it to just 550m accuracy is really bad, shoots around the target with a few hits ( deer sized). even 800m is poor with a few hits.

I'm running it suppressed with adjustable gas block.

Why is accuracy dropping so much at over 500m when it's perfect at 100m and 300m ?

 

[Jon Lester]

Re: Help !

If it is Key holing at 100, it will only get Worse with distance. First thing is finding out why it will not stabilize the 167s.
With that barrel it shouldn't be a twist issue,possible crown damage.

 

[WeaselWalker]

Re: Help !

I think veeramani might be incorrectly using the term "keyhole."

 

[veeramani]

Re: Help !

yes sorry I meant 3 shots touching each other at 100m and about 2.5 moa at 300m

 

[smokebomb]

Re: Help !

"Cloverleaf" is the term you mean. Keyholing is a lack of gyroscopic stability.

Sounds like improper parallax adjustment or wind causing your results. Unless its handloaded ammo thats loaded at 1400fps.

 

[veeramani]

Re: Help !

I'm using handloads of 167 gn lapua scenar at 265- fps.

I have a bolt action rifle with faster loads of 155 AMAX at 2950 fps, with no problems at the same range and even at 100m.

Strange !