How much of a difference does a head stamp make?

[Reece123]

Im getting into loading up some different calibers for some long(ish) hunting, 300-400 yards. My question is will different headstamps make a difference enough to be an issue? For example ive got a mixed bag of about 50 Winchester and 50 federal cases for my 243. Id prefer to load 100 at a time. Better off just buying new or once fired brass of the same brand? Same goes for my 6.5 PRC.

 

[Sizthediz]

I believe it makes a difference with case capacity. I would think it really depends on what you're trying to do accuracy wise. One ragged hole or paper plate accurate. Also the distance shooting 100yrds 500yrds. All factors that i think matter.

 

[Reece123]

Im good with 1 MOA at distance.

 

[pods8 (Rugged Stitching)]

Yes it can make a difference, whether it will make a difference if your specific case is another matter. The different cases have different internal volumes which will lead to different velocities at the same powder charge, if you have a hot load in a large volume case and load that into a smaller one you can have pressure issues also.

Just grab a bag of starline 243 if you're trying to save some money and don't want to buy premium brass, its decent / available / will all be the same. It removed one variable from your setup then.


If you were just plinking at 100yd I'd say load something conservative for a powder charge on the mixed headstamp and fire away. At range the velocity difference might cause you problems though.

 

[06 SB]

Each brand of case will have different capacity and will change the pressure of the cartridge. If you work up a load with the higher capacity case, then switch to the lower capacity, your pressure will increase. Changing primers, cases, powders (to include different lots of powder) or bullets requires another ladder. Also, using a round safe in your rifle may not be safe in another. Just get all the same headstamp. If you are not shooting past 300 yards, then any headstamp will be adequate. There is no reason to splurge on Lapua or other boutique brass.

The only way to deal with this is to develop a mild load so that the round is never over pressure...like factory ammo.

 

[270-300]

The technical answer is the case capacity, neck tension, and shoulder location will all vary slightly. Mathematically this hurts precision.

In practice, I dont worry about it. I know that is unbelievable for some people. In 300 win mag I can mix hornady, federal, winchester, and ppu head stamps. If i anneal them all the same, give them the same load of ramshot magnum and the same 200 grain speer hotcor, they will all shoot clover leafs together at 200 yards everytime.

In reality, me varying from day to day, and one gust of wind to the next have way more difference on bullet impact.

If i was a professional shooter with a career at stake I would worry about it. As a guy in wyoming who goes out and shoots elk at 140 yards, Ive got bigger things to worry about.

 

[Castle Rock]

Weigh a fired case from each brand , write down the weight then fill both with water and re weigh, if they hold similar weights have at it.
If the variation is more than say 5 percent it won’t do well

 

[Reece123]

Weigh a fired case from each brand , write down the weight then fill both with water and re weigh, if they hold similar weights have at it.
If the variation is more than say 5 percent it won’t do well

Tried this theory on my 6.5 PRC cases
Norma- 200ish grains empty
Hornady-220ish grains empty.

Case capacity was within 1 grain between the 2. Don’t remember which was which but one held 69 grains and 1 held 70 grains of water. Think they are similar enough to trust that they’ll be close?

 

[Blake C]

Even same brand different lot# makes a difference. Weigh some cases and you'll see

 

[WeiserBucks]

It only matters as much as you care.

 

[Smithb9841]

I have lapua and adg brass for my 6.5prc and see no difference in accuracy or velocity or anything else and that’s with a load on the hotter side.

My 28 Nosler I mainly shoot Nosler brass but have 20 or so hornady cases and don’t see a difference there but it’s a mild load for a 28 Nosler.

Load some up and try it there’s only one way to see if it’ll make a difference with your load and your rifle.

 

[Castle Rock]

Tried this theory on my 6.5 PRC cases
Norma- 200ish grains empty
Hornady-220ish grains empty.

Case capacity was within 1 grain between the 2. Don’t remember which was which but one held 69 grains and 1 held 70 grains of water. Think they are similar enough to trust that they’ll be close?

I would

 

[Woolley Bugger]

Not directly applicable to your rifle caliber question, but I load a lot of .38 spl with wadcutters. Starline brass accepts wadcutters beautifully, but with random range brass, sometimes, the taper is off so the brass can't accept the deep seated bullet without undue force and probably distortion.

I reload 9mm with range brass. I ordered some Starline brass for 9mm. I haven't loaded it yet, but I'm curious to see if I get better consistency with it than with random brass.

 

[Jack's Dad]

Don't be a cheap ass and mix head stamps. Part of reloading is maximizing performance by eliminating variables. Nothing says you don't give a shit more than being sloppy on brass. Just buy good brass and you can get exceptional life from them.

 

[pods8 (Rugged Stitching)]

Think they are similar enough to trust that they’ll be close?

Probably, that is why I said off the bat it may or maynot affect your specific use case. The reality is if you want to use mixed stamped brass and check to see if they are close enough to not have wild varations in velocity or pressure it can be fine. If you want to blindly load brass (esp. with a hot load) it may not be fine. For those that don't want to be bothered to check things getting some affordable brass from the same lot is going to save some potential headaches. You sound like you want to try mixed headstamp brass and check for differences, just do so paying attention.

 

[Chris in TN]

Case capacity and consistency matter. Headstamps per se do not, but headstamp is tied to the things that do matter.

I'd strongly prefer if all of my brass for any given caliber was the same, as much as possible, but if capacity and consistency is good between two brands, have at it. Sometimes it works out that way, sometimes not.

As for your specific example, 1 grain capacity difference on a 6.5prc sized case, is nothing, unless you're pushing pressure limits.