300BlkTalk

I'm trying to get back into reloading and starting first with a 300 Blackout load. I have some brass that has been once fired and has been trimmed to 1.340 inch in length. Is it too short to safely use or should I just dump it. The reloaded ammunition will be for plinking purposes only. I intend to load a low powered supersonic 125 Nosler bullet using 16.7 grains of 296, C.O.L. 2.060. I would appreciate advice as to what the absolute minimum safe case length is to salvage this brass, and if it may be other than the standard answer of 1.368 +0.000 -0.020 . Thanks.

Im new to reloading but i have trimmed and made around 200 blk cases if it was me and you lot of brass wasnt a huge lot i would trash it, if it a ton id load one light and try it if it works it wroks this maybe bad advice. like i said i'd trash it.

Has it been resized yet? The cases OAL will increase after they have been resized.

Brad

It has been resized.

I've heard it said, "You should have the same amount of neck length as the bullet's size in diameter." The 300 BLK has a pretty short neck at SAAMI max length of .266", so I guess that saying is thrown out the window! Your .008 under minimum and the cases will grow in length as you shoot them and resize. Your not going to crimp the case with the noslers anyway. I wouldn't be afraid of trying them.

Brad

Thanks for the reply Brad,

I'm thinking the 300 Blk case is seated in the chamber on the shoulder of the brass casing. You are correct that there is no crimping of this particular intended load. So, how much risk of errosion is there at .008 of an inch less then minimum case length? As has been pointed out, the subsequent firing should extend the currently short casing, hopefully to acceptable lengths. Is it worth salvaging about 100 rounds of brass without risking damage to gun or shooter? Neither of these outcomes would be acceptable and therefore would be the deciding factor if either one is a possibility. What do you think?

Basically you are losing .008 of bullet to neck contact point from minumum spec. Technically that will reduce neck tension and can affect runout. Neck tension can have an effect on bullet seating depths. If it is too low the bullets could be allowed to shift around in the case during transport, etc. The seating depth of a bullet can effect pressures. Runout is just that. The neck length helps to keep the bullet held straight. The longer the neck, the easier it is for the bullet to stay straight. If you feel uncomfortable about them call AAC and talk to a tech there. Rsilvers?

Brad

I also have some brass that is shorter than spec (I've gotten better at uniform trimming now). When checking brass length after resizing, I end up with 3 piles: 1) need trimming, 2) "too short", 3) perfect length (my definition of perfect is 1.35-1.36"). The need trimming is trimmed to perfect length. I use the too short for plinking loads. While admittedly my plinking bullets aren't as good as my hunting bullets, I've not seen any adverse effects of using too short of brass...my plinking loads aren't flying all over missing the targets, my perfect brass fired in the same chambers looks fine, my throat erosion gage shows no wear that would alarm me, brass isn't sticking in the chambers.

So, while I wouldn't use the short brass for accuracy testing or hunting, I'd certainly use it for practice, plinking, function testing. Note: I've not done chronograph testing with short vs perfect length brass, and that might be a good test to do.

For now I am just happy to get a small supply of plinking ammunition together. This supply of ammunition and rifle rifle isn't going to be used in the Tactical Olympics. It's a new build that I am trying to get functional. A small supply of reloadable brass for plinking ammunition would help. I think for my purposes and what stresses these rounds will be subjected to, the brass might still be worth salvaging. Thanks for the responses.

Tested the ammunition yesterday. No malfunctions, no misfires, no failure to eject, no failures to feed. For plinking purposes this concern regading case length turned out in the end to be a non-issue for me. Thanks for the replies. At least now I have a small supply of reloadable brass.