When using a published load, is it OK to vary the brass (Norma, Weatherby, Hornady, etc.) from previously shot ammunition as long as the dimensions are correct? I have brass from several manufacturers and I want to use loads published by Barnes.

Thanks.

Yes and no. There typically isn't to much of an issue but some brass manufacturers are thicker than others which can possibly cause pressure problems. Most published loads will be fine in any make of brass but some of the max loads could be close just watch for the tale tale signs of over pressure.

I would sort the brass into groups and not just shoot whichever brand I grab. Published loads are a starting point. To get the best results you really do need to do some load testing. A couple tens can make all the difference in the world. I can be a pain in the rear, but it's well worth the extra couple if hours to get it done. Just my .02

Like dee says, there are differences between manufacturers that result in variances in case capacity. Following proper procedure is the key to your success and your safety. When load development is carried out as it should be, variations in components won't hurt you because when you introduce a new variable, you back off the charge and carefully work back up to your accuracy & velocity standards watching for signs of overpressure.

Another thing to be aware of is that you'll run across a rifle now and then that won't allow you to get anywhere near the published maximums. I had a .243 that wouldn't let me go more than about a grain over the starting load, and maximum published loads would likely have locked that action up tighter than a drum. Maybe worse!

If you're tempted to mix your brass, don't. It's usually not a good idea, and especially if you're looking for top velocity OR accuracy.

Do you mean that the .243 started showing high pressure signs? Or was that just the most accurate load?

If I year you right, you are saying to keep the Norma Brass separated from the Weatherby Brass, etc. and work up from lower pressure keeping all variables consistent. If a variable is changed such as bullet type, case, powder, etc., start again at lower loads and work back up. This sounds pretty simple if it's adhered to strictly.

Thanks for the help.

I mean pressure. I use a chronograph to help determine maximum charge. If I see velocities that indicate I am near the max charge, I take it to heart. Velocity is a pressure sign, so to speak.

Most times military brass is much thicker and may require a reduction in powder. Also many rifles shoot marginally different with various components. I've had rifles that shot only 1 powder, projectile, primer and then not well. I have a TRG that's the other end of the scale. Try separating your brass and ck your loads at the range. Mostly I try to keep mine regulated to know when to trim or discard