Home Forums Hunting & Shooting Single Shots Contender Blackout project...

Lead is a good teacher.

No schitt...interesting. Glad to see you moving this project along. You aren't the only one learning some things, Muffin.

I've actually badgered out the bore-riding portion of a few double cavity bullets using lapping compound and a bullet with a screw in the base. I would just buy a new mould next time. It was a 6-8 hour affair to cast, prep lapping bullet, lap both cavities, clean, cast, measure, repeat several times. Both the moulds I did were aluminum, and both had long bore-riding portions. Both ended up being incredibly accurate bullets after the alteration.

Anyone ever done this????

Necessity being the mother-hood of invention, woke up this AM realizing that I am woefully understocked with Small Rifle Primers, and the current climate may mean they become even scarcer. I do, however, have a chitt load, by comparison, of Large Rifle Primers................. what to do???

Decided to sacrifice 10 of my 300 Blackout cases, got out the drill, chamfer/deburr tool, primer pocket uniformer.... and off we go.





It seems to have worked, loads are ready to test, maybe next week sometime..... DD????? A couple of primers seated pretty easy, none fall out, didn't lose any cases.

I do have a few questions:

1) Looked briefly online and couldn't find anything, Is there a handy tool made for this??

2) IIRC the 300 Blackout, at one time, was a wildcat..... Does this take it back to that status???

3) Thoughts?????

You happen to know the primer pocket wall thickness in the extraction groove?

I've never seen that particular variable attempted before. Seems there would be enough brass to be safe with these cast bullets shooting subsonic, but I'd not want to use them with full power stuff. I've got some picked-up 5.7x28 cases I should go measure.

SOOOooooo, got over to DDs range this AM, to shoot several 300 Blackout loads, one of which was the cases modified to accept Large Rifle Primers...........

As pictured several cases showed soot around the primers which is consistent with the number of cases that required very little pressure to seat primers,




this likely a result of the reaming technique and learning curve, about half did not show the sooting..............

Backed off of a previous load by about 20%............. Pleasantly surprised with the result.............

Will likely not persue LRP in the Blackout, but it is there if need be..........


7 shots at 50 yards - 10.0 grains RL-7 and CCI-200 prmrs

That's a cool project and nice to have that in your pocket for that day that it's needed.