7.62 x 39 with a short and tight throat

[Stoats]

Here is a nice conundrum for you:

my newly re-barrelled 7.62 x 39 has a nice tight throat on it, perfect for J-things. the barrel is .300 lands and .308 grooves.

Lee CTL312-160-2R as cast needs to be loaded extremely short to chamber. Once my .309 sizer arrives I expect to be able to load it a little longer, but not much.

The front part of this bullet is clearly intended to engage the lands.

This means that the gas check will be hanging out into the powder cavity. Is this a problem?

If this is a problem, is there an available mould of around 150-160 grains in which the front part of the bullet casts at just under .300 so that I can chamber the thing at maximum overall length? Would Lee's C309-160-R fulfil my purposes?

Thanks

[JIMinPHX]

I've loaded a few .223 rounds with the gas check inside the powder chamber. I don't like to do it just because it looks like a bad idea to me, but I had no problems when doing it. The rounds fired normally. When I pulled one of those rounds apart with a kinetic boolit puller, the gas check came right up to the mouth of the case before coming off the back of the boolit.

There was a group buy going on a 129-grain version of the Harris design boolit that might work well for your application if you size it down accordingly. Other than that, any .308 boolit that feeds well should work. I had feeding problems with any of the flat nosed designs that I tried in that cartridge. Even filing a meplat that was just over 3/16"on the front of a Harris boolit gave me issues.

[rockrat]

maybe the RCBS 30-165sil boolit might be the thing for your gun.

[MT Gianni]

My 155 gr lee has the gas check in the cavity to chamber in my Handi Rifle. It shoots better than I do. As it is a break open ss it is easy to check for a clean bbl.

[OBXPilgrim]

I've also got a 7.62x39 Handi & it shoots great with 180gr 311407 & the GC is sticking back into the case. Shoots nice tight little groups. I've got the Lee 160gr TL but I just load it for plinking. I doubt the 311407 would work for you, I can load the TLLee 160 seated out pretty good in my rifle.

[Stoats]

Thanks for the replies.

I have also considered -- shock horror -- paper patching a .301, which might do the trick.

Stupid question: if one were to create a plain-sided cast bullet that was basically a flat based version of a Sierra Match King which cast at .309, would it hold enough liquid alox to be adequately lubricated for use at under 1400 fps, or do you genuinely need the grooves when using this lubricant?