Thread: 308 case differences?

so, f/l sized some hornady match cases in my new lee dies, they were a tight fit in chamber of rifle, tried rp cases, same setting on die, they were good as,,, how is this so? i cant get any more compression to make the hornady fit my chamber, but the rp r fine, do i grind a smidge off the top of the shell holder?

Hi Antsman, had the same problem with my Howa 308 and Hornady SST ammo. They were slightly tight new when first fired in my Howa.
Then when I resized them to reload with my LEE die, they were still tight to chamber.
I then tried my RCBS small base X die I use for my BAR 308. All sorted! Cases now resized for both BAR & Howa.....

I suspect my Howa has a very tight chamber that requires that little bit more squeeze on the brass to reload?

When you say a tight fit do you mean the bolt was a little tight on closing? is this brass thats been fired in your chamber?(both RP and hornady)?

Give me the Hornady brass, that will solve the problem.

It will be the shoulder, as mentioned, you may need small base dies.
I had the same issue when I body sized some brass. FC was fine, but the LC needed the shoulder pushed back a smidge more.
I put it down to brass thickness. Since I've been full sizing it (for a semi), no issues.

Sorry brass is once fired in another gun .Yeah when closing bolt on rifle the hornady is tight as , but the rp is good

It does sound like headspace and you may have to take a touch off the shell holder.Do you have a way of measuring base to shoulder on the csae? and were the rp and hornady fired in the same rifle?

No I dont have any way of measuring that. And the brass was from different donors
I thought it was a headspace issue, and that my factory remmy must.be "toight" and that I should lose a smidge off the shell holder, just wanted to see what others said ,

Actually I can measure base to shoulder. I've got some digi measurer caliper things

Ok so you have some hornady brass that has been fired in a chamber thats longer than yours and some RP from a chamber thats been fired in a chamber thats the same or shorter.You will need to adjust your sizing die so that it bumps the shoulder back 1.5-2 thou. If your die is bottomed on the shell holder you can get get a little bit turned off the bottom of the die or the top of the shell holder. sometimes a different die will do the trick or you can get diferent height shell holders. Ill fill in a bit more in the morning.

Also just because the die is set to touch the holder deosnt necessarily mean it is when sizing at the cam over point have a look at the shell holder, there is probably still a small gap due to the press stretching a bit, if so you can come down a bit more with the die.

yep, aware of that Viet, shell holder was touching the case,,,,

Cams point is a good one, sometimes all you need is an extra couple of thou and a 1/16 of a turn in can often over come a little stretch and get that for you. But if the shell holder is hard up on the die then you have to make some adjustments. Its simply a case of your chamber being on the shorter end of the saami specs and your die being at the longer end. Taking a skim off the shell holder is simple enough and doesn't have to be precise but if you take to much you can weaken the lip and with a case thats a bit hard to extract from the die it can pull the lip off the holder. Some people prefer to take a bit off the bottom of the die instead. I have done a shell holder with a bench grinder and it will work but far better to get it machined off. When you set up again wind your die in no more than 1/16 of a turn at a time, size and check in the chamber repeat till it fits. Then check it with a fresh piece of brass. You are looking to bump the shoulder to give no more than 2 thou clearance but I like to feel a slight crush when chambering.

yep all of that makes sense to me , and is what i aim for. The i tried the hornady brass with the shell holder touching die , and the bolt wouldnt close, so i ended up winding the die down untill touching the shell holder, a bit at a time, then chambeing, the bolt would eventually close, but with a lot of tension, when i did same with rp, bolt closed no probs,,,

then the press(22 yr old Lee) broke

and before anyone else asks, yep ill prolly get another Lee, as they are cheap, do the job i require, and shoiuld see me right for another 20

Should have asked was the rp brass hard to chamber initially as well or has it been ok from the beginning?

the hornady was from two diff sources, as was the rp, so all from diff places, and outta the 8 fired caes i tried to chamber one allowed bolt to close, all the rest no matter which brand, failed to allow bolt to close at all, chamber must be toight ,,,