Thread: My 7mm PRC is driving me nuts…

Originally Posted by tibo

This was across 63.5 to 64.2gn I do call this a velocity nod…Attachment 259076

If you want to approach it scientifically with Brian Litz and Hornardy scientists instead of following the "I believe" crowd then be my guest.

Yes the above data shows you were producing excellent reloads, proven by a solid sample size. You don't say how that sample grouped but if it was good then there is something now wrong with the rifle and or scope, assuming you are following the same load procedure etc. I recently reported on the lose recoil lug in a Sako 75, was likewise hard to diagnose without specific advice, but fixed, it changed the rifle. Could have fired a gazillion groups with it without finding a "node".

I've never experienced a barrel "going bad" but in the way you are describing but I'd say it's1 a possibility. I'd be inclined to try some of your loads in a rifle that is a known shooter, that will eliminate one possibility with a 10-15 shot group. Then look at rifle/scope mechanicals (again) and if it ain't them, then all is left is the barrel.

Bedding ? Any shite in recoil lug slot ?

Nope, was my first check, my chassis is skim bedded, swap
Stock with another rifle and used another caliber in the chassis no change.

Does your head in that kind of shit. Even if you cant fix it its good to know whats causing it

Yeah mate it’s irritating

Correct a full case of 2217/67gns=3030xbang=dead deer

Can it shoot an accurate group at lower velocity? Different batch of pills?

Tried 4 different batch of ammo, even bumped into a faulty one, was measuring 0.2835 and half a mil shorter… tracked done some boxes of same batch number as the one that was shooting well. Unfortunately it didn’t solve it.
I went down to 2800fps during ladder test it didn’t group well and sd were on the piss. If I have to go below that in terms of speed to make it work I’d rather flick the factory 7remmag barrel back on.

@KiwiGreg I’m gona give you a call I think

Originally Posted by tibo

@KiwiGreg I’m gona give you a call I think

good luck with that

I’ve just had similar experience with a new 7 Saum.
Feeding from magazine with 2 thou neck tension Id get the odd flyer.
Single feed the same load and the flyers disappeared. Increased neck tension to 4 thou and can now feed from magazine.
I assumed under recoil the bullets were hitting the front of the mag box.

Originally Posted by Eastern Wander

I’ve just had similar experience with a new 7 Saum.
Feeding from magazine with 2 thou neck tension Id get the odd flyer.
Single feed the same load and the flyers disappeared. Increased neck tension to 4 thou and can now feed from magazine.
I assumed under recoil the bullets were hitting the front of the mag box.

Yep I was told it could be the issue, I tried single feeding. Didn’t work.

Random question, is the barrel fully secured into the action? No chance of anything moving mechanically? Suppressor is fully locked in, no wiggle at all? Is the barrel fluted, fully stress relieved and everything true in line? Bolt nose fitting the chamber end of the barrel, nothing weird there? Screws all clear of the bolt inside the receiver? Recoil lug not moving in the stock and receiver recess?

Something will be causing this, but finding it can be a mission.

Originally Posted by No.3

Random question, is the barrel fully secured into the action? No chance of anything moving mechanically? Suppressor is fully locked in, no wiggle at all? Is the barrel fluted, fully stress relieved and everything true in line? Bolt nose fitting the chamber end of the barrel, nothing weird there? Screws all clear of the bolt inside the receiver? Recoil lug not moving in the stock and receiver recess?

Something will be causing this, but finding it can be a mission.

Good point, will get barrel off and back on and re torqued, can’t hurt to try

I know sfa about precision shooting but couple of questions. Just food for thought. Does it shoot the two together, THEN the one each way??? Then what?? So if you were to shoot ten in a row doing nothing else would you have a group of four and two groups of three or two together( first two) then sprayed around like a mad woman's shit?? IF it consistently chucks first two together...what happens to subsequent shots if you stop and rum lightly oiled rag,then clean one through the bore???? Eg remove any light fouling before it builds up?? Your right it's still a very dead deer but not what you paid the big $$$ to achieve.