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