Differently sized M80 surplus projectiles

| February 5, 2014 | 0 Comments

Commercially manufactured 300 Blackout ammunition is very hard to find, and very expensive compared to the other calibers we shoot. I am in the process of handloading my own practice and defensive ammunition.

Based on prior posts over at the 300BLKTALK forum I decided to try the M80 military surplus bullets for our practice ammunition. They weigh in at approximately 147gr each and are fully copper jacketed.

I ordered them from Hi-Tech Ammo and were just a touch under $0.17 delivered each. Hi-Tech was great to deal with and processed my order very quickly.

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I was very excited to get started. I had done a lot of case prep work, researched my trial load data, and set up my digital scale and powder charger. I’ve reloaded at two other points in my life, but I’d never used surplus bullets before — only commercially manufactured projectiles.

I made my first fifteen rounds and checked them for overall cartridge length (COAL). To my surprise, there was a lot of variance in the COAL from one round to the next. I thought that my die was loose, so I checked and double checked. The two dummy rounds I made the night before were just fine, and I wasn’t sure what I was doing wrong.

I looked over everything again, and I couldn’t figure out what was wrong with my press or my setup.

Then it occurred to me to measure the M80 bullets themselves.

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I divided the projectiles into groups differentiated by 0.003″ increments. I did this for no reason other than it seemed like a good way to break them up.

As you can see, there is quite the variation, with a projectile as short as 0.089″ and one as long as 0.139.” That’s a pretty big variation when it comes to the length of a bullet.

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Luckily (?) most of the bullets range from 0.117″ to 0.125.” This will slightly effect COAL, but I don’t think it’s enough of a variance inside the case to cause a dangerous amount of pressure.

I’m still deciding what to do; I have never encountered something like this before with consumer-grade bullets.

I do know that I’m going to think twice before buying M80 pulls, though. Live and learn.

About the Author:

Short Barrel Shepherd Short Barrel Shepherd is a regular guy and works to make Web sites and mobile apps easier for people to use. He spends his free time attending fight-focused firearm, knife, and combatives training, motorcycling, writing, and playing games. His daily carry is a Glock 19 pistol and an AR15 .300 Blackout pistol in a backpack.
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