Ruger long range target in 6.5 PRC - short chamber?

[dysphonic]

Hi there
I am hoping that those of you with a ruger long range target in 6.5 PRC might be able to help me out.
I just picked up mine on the weekend and was surprised to find that when measuring the length to the lands with my Hornady oal gauge - that 0.020 off the lands puts my COL at 2.760 (with 143g eld-x) and 2.796 (with 142g Sierra March kings).
That puts it very close to the SAMI minimum of 2.755 and a long way from the Max of 2.955. In itself that may not be problematic but the bullet ends up being loaded very deep into the case.
Have others found the the ruger has a short chamber or is there something that I am missing?
I have loaded up a variety of test rounds with RL26 and there is no noticeable evidence of the powder bring compressed so far.

 

[dysphonic]

Anyone?

 

[Ckleeves]

It shouldn't be that short I think all factory 6.5 prc's would use the .188 (I think that's what it is anyway) free bore. If your shoot factory the 147 and 143 are going to be jammed if it's that short. Being that it's a new cartridge there shouldn't be any variations on factory rifles they should all have the Sammi spec freebore. If it was a custom I could see it having .130 or .150 FB but something isn't right.

I would clean the chamber and make sure your getting all the way to the lands, it doesn't take much to give you a false reading. Maybe try a few other methods for finding the lands also just to make sure the OAL gauge isn't lying to you.

If it is short it's up to you how you proceed, your probably leaving a little performance on the table and possible can't shoot factory ammo. Good luck.

 

[dysphonic]

Thanks CKLeeves for the comment.
I agree that something doesn't feel right. I did do multiple tests on the oal with the comparator (maybe 6 with each bullet). So the test wasn't a one off. I also tried pushing the billet forward as far as it would go and this resulted in it getting stuck in the lands - with no significant improvements in col.
I didn't give it a thorough clean so will try that before I head to the range on Friday.
really not sure what else to do.

 

[Ckleeves]

The Hornady OAL gauges can be kinda tricky with some throat angles it seems. It doesn't take much to get false readings. I think I would clean it good and then dummy up a round at factory length for that particular bullet and smoke it and try that. I think the factory offerings COAL should have about 50 thou jump with the 143 and 147 so it should be pretty easy to tell. Jammed with a 147 should be around 2.990-3.00 I would think.

 

[dysphonic]

Many thanks CK. I will
Give that a try in the weekend

 

[dysphonic]

Update for anyone reading this.
Gave the barrel and hire a thorough scrub and put 8 shoots through it setting up the scope.
Following another post shoot clean the problem seems to have disappeared and I am now getting 2.90 COL to touch the lands.
Much happier with this.

thanks for the help

 

[keithlashley]

Update for anyone reading this.
Gave the barrel and hire a thorough scrub and put 8 shoots through it setting up the scope.
Following another post shoot clean the problem seems to have disappeared and I am now getting 2.90 COL to touch the lands.
Much happier with this.

thanks for the help

Did you try and run any factory ammo in it mine is hanging in the lands with factory eld m and eld x will not eject a loaded factory round

 

[bullfrog]

I ran into the same problem with a RPR in 6mm Creedmoor. After a few rounds it went away. I assume the very tight throat clearance along with a few burrs from reaming was the culprit.

 

[keithlashley]

I ran into the same problem with a RPR in 6mm Creedmoor. After a few rounds it went away. I assume the very tight throat clearance along with a few burrs from reaming was the culprit.

I think my problem is a little worse than that when I got it out you can see rifling marks on the bullet I had to use a cleaning road to get bullet out of lands