300 Blackout - Long Neck

[rosst]

152679

Hi guys . .. i would feedback on this idea, maybe its been done before i just haven't seen it.

here goes . .. instead of trimming the case after forming as in the top pic, how about blowing the neck out . .. to a long neck, similar lookn to the lower pic but with a 30.cal neck . . for boolits, a .30/30 neck on a .223 case

this would be for bolt actions of course like the Rem700 short action i see in 300BLK.

maybe i've had to much coffee and to many split shifts . . any problems you can see or advice before i talk to my gunsmith . . or even better has someone else done it so reamers/dies are available

the reason i'm thinking along these lines . . i'm looking for the perfect subsonic and higher velocity ( 1600fps ) rifle for boolits.
i've tried .308 & 7.62x39, the necks are to short for my liking, using a chopped .30/30 now which is close to perfect for hunting but a Rem700 bolt action would be preferable for what i want to acheive.

thanks in advance . . . R.

[GhostHawk]

You do know they won't fit like that without either trimming or a ream job right? If you want them long,try looking at the .30/223.

It all comes down to chamber dimensions and specs.

It is not like a Handi rifle in .357 mag that can also take .360 DW brass because of a long factory lead.

And remember that bullet is probably not going to fit flush in that neck, it is going to stick up some, so allow for that when you are measuring.

The easy answer is a pound cast of the chamber (how to is in the stickies)
You can run them somelong, how long will depend on barrel.

[dilly]

Isn't one of the 30 XCB's features a longer neck? I know outs from a bigger case, but have you looked at it. It would give you an excuse to get a rifle from goodsteel, and he sure does good work.

[rosst]

was thinking neck turning would be a must after fireforming, had'nt considered inside neck reaming but if it has to be done it has to be done.

30-223 has'nt got the long neck i want GhostHawk, i've been spoiled by the .30/30 .. as far as COAL goes there should be plenty of length in a short action for the bullets i want to use - 165 NOE, Lyman 311041, RCBS 180FP

i just reread the 30XCB thread again the other day dilly . . all 40 odd pages over 2 days. .. . which got me thinkn.
while the 30XCB is a great idea its not me for a couple of reasons, NO more new rifles, its taken me a few years to cut them down to 12, it'll have to be one of 2 short actions i own now, a .308 or a .223 Rem700 being the best candidate.
my ideal choice would be just push the shoulder back on a .308W that would still give the 1600fps i want . . . i 'll discuss that with my gunsmith when i see him later in the year.

[dilly]

So smaller than 308 with a longer neck. Maybe if you drew your inspiration from 300 Savage brass conversion and didn't cut it down so much to shorten the neck?

[rosst]

being in New Zealand there is the problem of availability of cases, 300 savage would be considered exotic here, not unheard of but rarely seen even by enthusiasts .308 or .223 would be my first choice of parent case, once fired .223 in bulk is very cheap here .. . as i say ' its just an idea ' cheers for the thoughts . .. R.

[paul h]

being in New Zealand there is the problem of availability of cases, 300 savage would be considered exotic here, not unheard of but rarely seen even by enthusiasts .308 or .223 would be my first choice of parent case, once fired .223 in bulk is very cheap here .. . as i say ' its just an idea ' cheers for the thoughts . .. R.

Should be pretty straightforward. The smith can run a necker/throater into a 300 bo chamber to allow for the longer neck and most likely a standard set of 300 bo dies will work. You'll need either a custom trim die for the brass, or modify a .308 Lee trim mandrel to get the depth you want.

[popper]

I assume the long neck is to keep more of the boolit in the neck so heavies don't leave the base below the shoulder? The 40WT lengthens the case but shortens the neck - aim is more powder under a 125 bullet. I'd like the slightly longer case AND longer neck. Another choice for you might be the 30HRT.

[nekshot]

if it don't work, put a reed in it and blow---a goose call maybe? Hey, I do like your idea and also taking a 308 and run it into a 300 sav gives a nice long neck also but more storage room than you are looking for.

[rosst]

Should be pretty straightforward. The smith can run a necker/throater into a 300 bo chamber to allow for the longer neck and most likely a standard set of 300 bo dies will work. You'll need either a custom trim die for the brass, or modify a .308 Lee trim mandrel to get the depth you want.

thats what i was thinkin pual . . . like this

http://images.fishnhunt.co.nz/images/Rossi45/300blkln.jpg

[rockrat]

Kind of like something like this? Made it about 27 years ago. To use shooting at the Coors Schutzenfest(sp?) and later in IHMSA. 357max with a 30-30 ish. length neck. Used the reamer on a barrel for an xp100. Cases were a bit bulged at the base, but shot well and had no trouble with cases. Resized with a 357mag die and neck with a 30 luger die.
http://i34.photobucket.com/albums/d149/Bigdog337/001-6-3.jpg (http://s34.photobucket.com/user/Bigdog337/media/001-6-3.jpg.html)

[rosst]

kind of exactly like that rockrat . . that is one good lookn cartridge, did you give it a name ? . . . i'm thinkn ' Longneck'd RockRat ' maybe to early and to much coffee . . . cheers

R

[rockrat]

I called it the 30 silhouette. length of the case from the rim to the shoulder is a 357mag case length.

I have thought about having a 300 blackout reamer made, but with a long neck and using full length 223 brass, just like you are contemplating. Would be a dandy.

[ProfGAB101]

I had a different case combo planned for the same reason - longer neck to better support cast & lubed bullets keeping the lube out of the powder.

My idea was to use a 223 case formed like a 7.62 x 25 Tokarev but with the neck about 8mm - (5/16") long and call it a 300 Carbine for rebarreled M1 Carbines with some decent twist... Goal was a 150gr round nose flat point 30-30 style cast bullet that could feed from the normal M1 Carb mags using cheap parent brass and give the baby M1 better knockdown.

Reloading your own could be done cheaper than buying 22 rim fire, and more fun to shoot + it would be a great suppressor round.

[rosst]

153193
next thought . .. as paul h said about a gunsmith running a reamer/throater to make a long neck possible, if thats workable . .. . i might just look at the .308 longneck as the better way to go.
i was originally thinkin of pushing the shoulder back to get the longer neck . .. this would be a kind of smaller version of the XCB project
i should be able ( maybe, i dont know, i am getting ahead of my pay scale here ) be able to use a bushing die for the neck and a reamed out .308 FL die to size right down if i have to . . .. what do you think ?

the cartridge in the middle is a loaded for my .308 using one of my favorite boolits for hunting in subsonic and at 1600fps, either the 170 lyman or 197 RCBS.
My big problem with this setup is the idea of the lube sitting out in the open like a grit magnet and then going down my barrel doing all kinds of nasty things.

[rockrat]

I think a long neck 308 would work well indeed.

You could also run a neck/throat reamer in a 308 chamber and use 30-06 brass. You could get a real long neck then


Or maybe use 6.5 x 55 swede brass for a bit longer neck than the 308

[rosst]

http://images.fishnhunt.co.nz/images/Rossi45/ln2a.jpg

well this is interesting . .. .

just annealed a 8X57 case
put heaps of lube on and crossed fingers
ran thru a .308 trim die
thru a Forster neck bushing / shoulder bump die
M die
197grn. RCBS seated with a 30/06 Lyman sleeve die
LEE crimp die
compared COAL to my .308 boolit loads
and BIG smiles . . boolit is completely covered and bullet base just ends at the shoulder

[r6487]

308 brass ran thru 308 x 1.5" forming die gives a long 30 cal neck, rcbs still makes all the 308 x 1.5" dies