Reduced OAL...Still Safe?

[Muskrat]

A buildup of bullet lube during a long loading spree gradually reduced the OAL of my 10mm loads down to 12.310 before I caught it.

I'm loading Rim Rock 220 grain (226 grain when you weigh them) hard cast over 6.1 grains of Longshot. My powder measure never varies by more than .1 grain and I weigh regularly, so the max load would be 6.2 grains.

It's a pretty mellow load...right about 1,000 fps from a 6" KKM barrel, when correctly sized. I'm not super worried, but I've never loaded reduced OAL loads before, either.

Any input?

thanks!

[The_Shadow]

It's not likely at 6.2 grain load that the pressure rise would be that substantial...   Yes several things can build up in the seater plug with lube from the cast bullets being squeezed up when crimping or if lube or debris is on the bullet's nose over time.  Good catch!

[sqlbullet]

Concur.  With a load that light, you should be fine.

[Muskrat]

Thanks guys...I though it was probably safe, but I don't have any experience with reduced OAL loads so I'm glad I asked. I actually caught the reduced OAL by sight. The bullets just didn't look quite right compared to the earlier loads.

FWIW, I've really been enjoying the 220 (well, 226) grain Rim Rock bullets loaded to around 1,000 fps for plinking, steel challenge, and USPSA shooting. It's overkill for USPSA, and super-overkill for steel challenge, but if you're going to shoot a 10mm you might as well make some noise...

My current favorite load is the 220 Rim Rock over 7 grains of Blue Dot, as it's very accurate out of my barrel. The big run of Longshot I just loaded is due to having more Longshot than anything else on hand, and accuracy doesn't matter as much since all shooting matches are over till spring where I live.