Encore 7mm Rem. Headspace

[leadman]

I have an Encore with a 7mm Rem barrel that is giving me problems.

Most of the brass will enter the chamber and be anywhere from flush with the end of the barrel to .003" below the end of the chamber with the extractor removed. There is also .004" gap between the end of the barrel and the breech.

Some brass when fired shows a small bulge in front of the belt so I suspect the barrel is chambered too deep. The shoulders on new brass do not touch the shoulder area in the chamber either so I end up with a very thin spot in front of the belt. This has lead to case seperations on second firings.

I have fireformed the brass with 15 grains of Unique and COW with a wax plug and is a little better, but the brass still thins in front of the belt.

I think I know what is wrong but need a dimension of how deep the recess in the chamber should be for the belt.

Is there also a SAAMI spec for the distance from the belt to the shoulder? I looked at headspace gauges by these do not include the shoulder area on them, as headspace is supposed to be controled by the belt.

The headspace in this barrel seems to be controlled by the extractor as it holds the case back enough so it will fire. This is why you can fire 45ACP in a 45 Win mag Contender barrel.

Does anyone have a belted mag headspace gauge to give me the dimension from?

[Nobade]

SAAMI spec is .220" Min, .227 Max. This is too long though. I made a gauge that is .2175 and use that. This way the case is headspaced on the belt and not floating in the air like factory chambered belted mag guns are. Cases are normally .215-.216. I consider the GO gauge to be a No-Go when building guns, but of course all factory guns are chambered so SAAMI spec.

For best case life my recommendation would be to neck the cases up, then full length size until the gun will barely close and fire form with cream 'o' wheat. Then just neck size, and they should last fairly well. The bulge just ahead of the belt is normal, most chambers are big enough to let this happen.

[leadman]

Nobade, thanks for the specs. I measured my barrel and it is .223", but with the .004" to .005" gap between the barrel and breach I am at max or beyond.

I also measured some of my brass and the belts on most are .213 to .216".

I think I will call Nosler and ask what their belt dimensions are. If they can't tell me or are on the small side I might anneal some 300Win mag and size it down until I get about .0005" headspace clearance. I have a Bellm dial indicator to do this with the extractor removed from the barrel.

I had my Dad's old Rem.700 in 7mm Rem Mag with the blued stainless barrel and it was a very accurate gun and no problems with the cases. Guess back in the early 60s when this was built someone knew what they were doing. I passed this on to my oldest son when I bought the Encore. Should have made him wait until I kicked. LOL.

Too bad Marlin 450 brass isn't longer. I could custom cut the belt on it to fit my gun!

Would be nice if a sleeve to fill in the belt area of the chamber would work, then just turn off the belt and headspace off the shoulder like I try to do now.

[giz189]

Leadman, according to Mike Bellm, normal headspace gauges don't work on T/C single shots. Go to his site at at Bellm t/c and search on there and it will give you a detailed description of how to check the headspace on the Encore. It is very easy. He also talks about the gap between the barrel and the breechblock. Hope this helps. Leadman, didn't read all your post, guess you already knoow about Bellms.

[475BH]

I have a 7-30Waters barrel for my Contender, and have used 30-30 Win. cases.
Forming to the chamber is a lil extra work but works good.
Sounds to me you just have to load your bullets a lil long so the rounds will "crush fit" into the chamber, seat the bullets out to fit tight when closing the action. Then the case will be tight against the breach and wont move when fired.
You cab use a cheep bullet or cast and a light charge (cast bullet data).
Then you have to set your sizing die (FL if used) to not move the shoulder back, or just touch it.
The cases then should last a long time, I have some 30-06 loaded 10 or so times and still good.

[redneckdan]

I would size the case up to .30 cal or .338 cal then size back down with your normal sizing die like another poster mentioned. Another option is to seat a bullet way out so that it forces into the throat and keeps the base seated against the breach.