.308 loading for new Bergara HMR Premier Pro

[Morrey]

I've reloaded a few years but would be considered an occasional or seasonal (hunting) reloader. I have RCBS dies for my RCBS single stage loader(s). I have two loaders so my sizing/decapping die stays in its loader, and the bullet seating die stays in a separate loader. I stick to .308 so not much swapping around goes on.

I had loaded for a Ruger AR-10, so the dies were adjusted for that gun's chamber. But when I size and de-cap brass for this new Bergara, the bolt wont close on the sized and trimmed brass. I tried to push/seat the shoulder a little deeper but doesn't seem to help.

I had a factory box of Remington .308 and that factory round chambered properly, thereby I know the gun's chamber seems ok with factory ammo.

Any suggestions what to adjust to get the brass to fit in the new Bergara? The brass is trimmed to length properly, so I guess the shoulder is the problem?

 

[Walkalong]

Keep adjusting the sizer down until the brass chambers.

This video on utube shows how to find the lands on your rifle for a particular bullet, but you can also use it to set up your sizer for your brass and that rifle. You'll need some way to measure the shoulder position so you can replicate it.

Most people do this for sizing without removing the firing pin assembly or the ejector, but you will get better results if you do. If you don't have what you need to do that, just adjust the sizer down a tad at a time until it chambers.

Since you will be loading for more than one rifle you will want a way to measure where the shoulder is so you can size to fit each rifle, or just size as much as is needed to fit both.

Either way, this is an opportunity for you to up your game in setting up sizers.

 

[Walkalong]

Here is a pic of me checking shoulder position on 300 BLK with a home made " shoulder gauge".

Various gauges to do this range from $20 to $60 or more. If you have a Wilson (etc) case gauge you can use it and calipers to do this.

 

[Rod47]

You really need to meaure the length from base to datum line on a fired casing from each rifle. I use a Hornady tool. Set your resizer for the smallest dimension and then use Skips Die Shims to rsise your die for other rifles.