Friday, April 12, 2019

That just doesn't sound right

for 10k rounds of anything:
Test Results
1. Rifle was shot to 10,000 rounds
2. No throat erosion was detected.
3. No rifling wear was detected.
4. No gas port distortion was detected.

Saying these bullets caused no more, or less, wear than standard designs would be one thing, but some of the wear in those areas comes from propellant gas, and I'm not sure how a less-wearing bullet would prevent that.


markm said...

The bullet weighs 45 grains, compared to 55 for the original M-16 ammo (and I think the most common civilian .223 load) and 62 for the present M855A1 GI round. That will reduce the peak chamber pressure and some forms of erosion. They may have also reduced the propellant load.

Firehand said...

Reduced wear I could see, but they keep saying 'NO wear', and that I have a problem with.

markm said...

For anything with moving parts, "no wear" means they didn't look hard enough or didn't run the test long enough. It's an exaggeration, but in many cases it's close enough that I wouldn't argue about it.

I think the relationship between chamber pressure and throat erosion is close to exponential, so a modest reduction in pressure can give a great reduction in erosion. You might fire 10,000 rounds through one gun over a few years just to remain highly proficient, but few worry about whether the chamber and barrel can take 100,000 rounds.