dig4gold

I'm getting a Thompson Center Encore pistol in 7mm-08. I have a lot of .308 brass. I've already done a few and taken some measurements. Looks like it should work.
Any precautions I should be looking for? I also have .243 brass that I could resize to 7mm-08. I suspect most of you will think the .308 to 7mm is better than .243 to 7mm. One is compressing, the other expanding (thinning). Any problem doing the .243?
An obvious thing I thought of . . . how do I distinguish the .308/7mm brass from my .308? Is there a preferred way to mark or label the re-sized brass to keep them separate? The 7mm-08 brass will still have the ".308" stamp on the headstamp. (Or .243)
An obvious solution; don't work on both at the same time.

Nomercy448

I prefer to make my 7-08 brass from Lapua Palma brass, giving me access to small primers. Simple neck down. 243win pulls up to 7-08 just fine as well. Don't use the expander ball in the sizing die, use a bushing full length sizer and neck down, followed by an expanding mandrel die. For 243win brass, I work the brass more because I expand the neck with the mandrel first, then full length bushing, then mandrel again. I use at least two steps of expanding mandrel to make that change, sometimes 3 steps - 25cal, 6.5mm, then 7mm. The more you ask it to expand at a time, the more apt it will be to pull thin spots and eccentricities between the neck and body. So I take my time, neck up 2-3x, reset the neck tension and re-center the neck to the body, and then re-expand to 7mm. 243win brass can also leave a doughnut at the base of the neck in some brands, as you're pulling shoulder out into the neck. So that's at least three advantages for using Lapua 308 Palma brass - easier sizing, less likelihood of doughnuts, and small primers for longer life.

Lots of options for marking your brass.1) Use 1 specific brand for your 7-08 loads. 2) Stamp an indicator into the casehead of all of your converted brass. 3) Paint a ring of automotive or modeler's paint around the extractor bevel of your converted brass. 4) Use a file to carve a small notch in the rim of the converts. 5) Sort at the bench by slipping the tip of a loaded 30cal round into the neck... Lots of options, some work better than others for different folks...

Usually, I keep my stuff pretty well segregated, so marking isn't critical for me.

Mr. Slim

it would be easier to just buy 7mm-08 brass to start with. its not a wildcat rifle so 7mm-08 brass should be readily available. less chance of a mix up.

dhasemann

I think he is trying to use .308 brass he already has to save some money.

Ridge Runner

it'll work fine just watch neck thickness, when ya neck down it gets thicker when ya neck up it gets thinner.
RR

bronko22000

I've necked down many a 308 case down to 7-08 without any trouble. Same as necking down 30-30 brass to form 7-30 Waters for the Contender.

Mr. Slim

the point is he said he owns a 308 rifle and the chance he could mix them up could happen. my one brother had a 6.5-06 that he wanted me to load for but had to either use 270 or 25-06 casings to form the 6.5-06. he owned a 270 rifle so to keep from mixing them up we used the 25-06 which was easier to size up as 25 caliber is closer to the 26 caliber.

Ridge Runner

270 case is also too long would require trimming.
RR

bronko22000

Many times I've taken similar guns/cartridges to the range. I follow a simple rule. One rifle one ammo at the bench at all times. And if you have the same model rifle, check that data stamp and double check your ammo. Verify and double check.
I've witnessed a guy shoot a 7-08 out of a Sako .270 win. We were shooting 2 silhoutte matches at the same time (hunter and unlimited (I think)) I was spotting for him and his 5th shot at the turkeys his bullet hit 100 yards short! When he opened his bolt it looked like the case separated at the shoulder. But after checking the head stamp we found it was a 7-08 round. Fortunately for him and possibly me the Sako is a strong action and all that he suffered was a broken extractor.

RichardMillans

Interesting