Tolerance in Brass

This is the last of a five part series on tolerances in reloading.

In previous sections we’ve looked at tolerances in the weighing of the miniscule amounts of propellant we use in handgun ammunition, the COL and crimp measurements we check frequently during reloading, and in the critical nature of bullet weight.

In this the final part, we take a look at brass to find out how we can make sure the ammunition we make will function reliably during competition when a mis-fire or chambering problem means an alibi string and possible loss of those vital points.

In my early days of reloading 45 ACP for my tight-chambered wad gun, I learned that all brass is not created, or bent, equally.

I learned the hard way that some brands of new brass had primer pockets at one end of the tolerance range whereas the primers I was using were apparently at the other end. Result? Lots of high primers that wouldn’t go bang on the first strike.

I shot a lot of alibi strings until I purged that head stamp from my supply.

And I learned that once-fired brass can be a problem if it was fired in certain brands of firearms, Glocks in particular.

The brass resizing die is called a “full-length” resizer but, in practice, it doesn’t quite do the job. Commercial reloaders use a rolling resizer in contrast to that found in most non-commercial equipment. Rolling resizers can take out a bulge down near the base of the shell because it “rolls it to size” many times. That repeated resizing works whereas the “once through” action of non-commercial equipment just doesn’t cut the mustard.

Glock-fired brass won’t work reliably in my wad gun no matter what I do.

The best tool I found for brass is the Martindale Gauge. You’ll find several posts here where I’ve written about it before.

New brass that I shoot in my guns — I don’t have a Glock — doesn’t need to be checked. But if I buy used brass from some other source or pick it up at the range, I will have to run each shell through the Martindale Gauge.

My rule is simple.

  • Pass Martindale Gauge? Reload it.
  • Fail the Martindale Gauge? Toss it.

Does Bruce’s gauge reject more brass than it should? This is possible. Before I started using Bruce’s gauge, I was able to reload and shoot a lot of brass, some of it from Glocks.

But at that time I also suffered an annoying number of problems and, after culling the brass with this gauge, those problems were gone.

So I’ve learned. If there’s any question about brass size or shape, I run it through the Martindale Gauge. If it don’t pass, it is gone.


Final Observations

Although I’ve been shooting Bullseye for a few days more than seven years, I still consider myself a newbie.

I have a lot to learn.

But along the way, I’ve picked up a couple of lessons. One of them is that, in this sport, you need the very best equipment you can get from top to bottom. That includes the guns you shoot, the supplies you purchase when reloading, the reloading press itself and the measuring instruments you’ll use when pulling the crank. Skimp anywhere along the way and you’ll be shooting alibi strings and getting angry at your equipment and ammunition rather than paying attention to that red dot or the front sight.

If you can’t afford top quality equipment, keep saving your pennies until you can. Don’t buy something half-way with the thought that, “When I get good I’ll trade up.” The simple fact is that, with bad equipment, you can’t get good.

Good equipment is a truth-teller. When a shot goes astray, good equipment says, “Not my fault.”

And if the equipment is not at fault, then …

You know.


Here are links to all five parts in this series:

  1. Tolerance in Reloading (Introduction),
  2. Tolerance in Powder Throw,
  3. Tolerance in COL and Crimp,
  4. Tolerance in Bullet Weight, and
  5. Tolerance in Brass.

See you on the line!

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