New reloader questions.

[powereng]

Got a couple of newbie reloading questions, so bare with me here.

First off, due the the shortage of reloading supplies I've been grabbing any 308 components I can get my hands on. So my first questions is, is there any major difference between the Federal Magnum Rifle Primers(215) and the Federal Gold Medal Match Magnum Rifle Primers(GM215M)? I going to assume it has more to due with the consistency of the manufacturing process more than anything else, but thought I'd ask.

Second, a buddy of mine told me that using a Magnum Rifle Primer over a Standard Rifle Primer will act as an added 3.0 grain of powder to your overall powder charge. I can kind of see his point, but wanted to check with those in the know.

Third I've been using a Sinclair comparator with bump gauge insert to measure my case shoulder. With the comparator on my caliper, I close the caliper jaws and zero out my caliper. Next I run the case through my FL re-sizing die(Redding Competition series). I then put the case back into the comparator to get my shoulder measurement. Since I'm starting with a new rifle (GAP10) I'm trying to get my brass, shot out of a different rifle, back to SAAMI spec. I'm currently coming up with a head to case shoulder dimension of anywhere between 1.5585 to 1.5600. So two questions, one am I using the comparator tool correctly and two are my dimensions in spec.

Thanks for all you help guys. Powereng

 

[fish30114]

Re: New reloader questions.

Hello there--welcome to the obsession!

As to your questions re: primers, I don't think there is a pat answer to how much a mag primer affects your charge relevant to a specific amount of powder, but in short, yes a mag primer compared to a standard primer does make your load a little more stout, ALWYAYS us the tried and true practice of starting low with your powder charge and work up. Anytime you change a component of your load you should work up like from scratch.

And yes you seem to be using your shoulder measurement gauge properly. All you want to do is set your die to bump the shoulder back about 1 or 2 thousandths. This gets the brass sized minimally to fit YOUR rifle/and this requires brass fired in that particular rifle, if it doesn't fit in this rifle without significant sizing, I'd start worrying about whether or not the chamber in this other rifle is to spec--and in this case the SAMMI spec is not important. In fact other than perhaps establishing your trim to size, you don't have much need for SAMMI specs, when setting up your dies etc.


Good luck, I'm sure you'll enjoy that GAP rifle!

 

[powereng]

Re: New reloader questions.

Good to know Fish, Thanks.

With my primer, I haven't loaded a single round yet, so I'm starting my load work up from scratch. I have access to both types of primers, so I guess I'll just have to pick one to start.

With my brass, all the cases I have on hand were fired out of my Noveske N6. Before re-sizing most of the cases measure 1.5585. For the few pieces that I have that are over that dimension, with my die turned all the way down to the press ram in the fully extended position, the shortest I've been able to re-size has come out to be 1.560. My N6 must have had a super tight chamber with regards to SAAMI spec. I have a bunch of new factory FGGM, so I think I'll go out and fire a few boxes and find out what my chamber dimension is on my GAP10 and start from there.

Thanks again for your help.

 

[fish30114]

Re: New reloader questions.

Yeah Powereng, that is interesting on your brass from your N-6. But I will tell you that I have had to sizing dies over the years that I had to grind a few thousandths off of to get them to size my brass sufficiently. Won't really know that til you get some fireformed brass out of your GAP... if you end up having to size your brass a little more than the die will actually give you, don't sweat it too much, I just took a skoche off of those two dies I mentioned with my belt sander and they worked fine from then on. In fact if I was sizing them for that N-6 that's exactly what I'd be thinking about doing.

Regards, Fish

 

[BIRDHUNTER]

Re: New reloader questions.

To be honest I wouldn't mess with brass fired out of a non match chamber much less an autoloader. Buy some new Winchester or Lapua brass and keep it with that rifle. This alone will give you much better accuracy and consistency.

 

[Sniper Uncle]

Re: New reloader questions.

Powereng, I am no expert, but I took a class from a Master Reloader. He strongly suggested that I only use Magnum Primers in Magnum casings. I suspect that there is a reason that they make magnum primers different that regular ones. I have seen in my manuals a couple places---can't cite just which ones at present----that the manual called for a magnum primer with a certain powder in a certain non-magnum casing.
I personally would only use magnum primers in either magnum casings, or if the manual called for them for a specific load.
As far as Match v. non-Match Primers. In any manufacturing process, there is spec tolerance. The closer to the original spec----ie. the less tolerance used---the better the product and more consistent. The Match Primers are made to tighter tolerances, and thus more consistent. Some Primer Manufacturers do not offer a Match Primer, as their tolerances are tighter to start with. They often cost just a bit more than the competition non-Match Primers. They would be worth it.
If you want consistency, or want to shoot competition, go with either the Match Primers, or with the company who doesn't offer match primers. I personally am switching from Federal (who offers both match and non-match) to Winchester and CCI, who don't.
Whatever you do, make sure you research your loads well and don't interchange magnum primers with non-magnum primers unless you know what you are doing. Better safe than injured or dead.