Bottlenecked cartridges

Status
Not open for further replies.
F

Futo Inu

New member
yes, like 357sig and 400 corbon, etc.

Since these have come on strong as of late (mostly due to the over-10 mag ban), I think it may be time for an extensive discussion of their pros and cons, as it seems quite a few shooters here have had a chance to try them out.

If not an extensive discussion, I specifically want to discuss the reliability factor, which is one of the primary factors attrributed to necked rounds (theoretical enhanced feed reliability due to the smaller bullet in a larger chamber throat). I have come to the conclusion, however, that at least with the .400 corbon round, actually the opposite is true. It seems less reliable than even its parent round, the 45acp in my pistol. The reason for this is the way the rounds stack in the magazine. The more rounds you put in, the more and more they scrunch together at the front, causing the round to take a major nosedive when the round above it is fed, which causes a low jam on next feed. I thought this was a problem in to my mags (affecting both calibers) until I put the 45s back in, and NO jams. I thought I had found in the 400 corbon the perfect defensive round (in light of the full-cap mag ban, anyway), but alas, Murphy's law has kicked in. Now I'm back to 45acp and feel much more comfortable, but still not entirely satisfied with it. I think for me, 45acp is the best defensive round there is, but wish there was a better one (same size or bigger hole, low pressure, with the inherent feed reliability of say a 9mmP). Guess I'm still in the "cartridge search" mode. Well, got to do something to fill my thoughts.
 
Futo:

I guess what your experience means is that the .400 CB is not reliable in YOUR PISTOL. It could be totally reliable for someone else. I don't own one and can't give you any personal feedback on it.

In my case, my SIG P226 .357 has never experienced a failure to feed. For me, it is the most reliable semi-auto I've ever carried, and that includes a couple of custom 1911 .45s from two well known smiths. Some one else out there may be having feeding troubles with their .357 SIG. For me, I have more confidence in my 226 than my other two SIGs which only experienced failures to feed due to bad magazines (220) and bad ammo (229).

But I don't know if I can legitimately claim that this pistol's reliability is due to the bottleneck design of the .357 SIG. Who knows....?

Mike
 
Futo,

I'm afraid I too must take issue with your conclusion. The .400 Cor-Bon has been extremely reliable in my pistol. Seems I recall a number of articles on the virtues of bottlenecked cartridges published around the time the 357 SIG was introduced. Unfortunately I recently purged my then burgeoning collection of magazines, so I won't be able to find them. Suffice it to say that the bottleneck was uniformly considered intrinsically a better feeding design for a cartridge.

-=[Bob]=-
 
Futo,

Here's one potential drawback of a bottlenecked pistol cartridge to consider:

Pistol cartridges aren't very long. This means that the case neck of a bottlenecked pistol cartridge isn't going to be very long either. With a relatively short length of brass holding the bullet in place, the risk of the bullet being pushed back into the case and raising pressures (perhaps catastrophically) increases.

This came to my attention when I read some messages on another board (UGW) regarding someone who had a kaBoom shooting .400 CorBon in his Glock 21. A round hit the feed ramp nose first, the bullet was pushed back into the case, and...

I don't think that this is a fatal flaw, but it's something to consider. And I'm still waiting for the .38/.45 (.38 Clerke?) to make a comeback!
 
Futo,

My Colt Government Mk IV Series 80 that has been heavily customized as proved extremely reliable with .400 Cor-Bon. Never had a failure to feed or any other problem. I've had mine barrel conversion since the round was introduced at a SHOT Show a few years back. My original barrel was improperly machined with a chamber that wouldn't take the round and the maker (now out of business) had to swap it out under warranty. But since that was fixed no problem. I use Chip McCormick magazines and I handload my ammo using Starline brass. I also acquired a Corbin cannalure tool which I used on some bullets at one point... I rarely bother anymore as the Redding dies give a very secure crimp.

As you realize, the fact that my particular gun has proved reliable doesn't mean all 1911A1s will prove equally so. My thoughts are that a properly setup gun with fully supported chamber, good magazines, etc., and well prepared ammo should serve very well.

I use a fitted Bar-Sto barrel for my 45ACP use in this same gun... again flawless performance.

-=[Bob]=-
 
Matt, it does sound like the bullet being pushed back into the case would be a problem with an improperly crimped round, not an inherent design flaw of bottlenecked pistol cartridges.

My own experience with bottleneck is exclusively in the realm of the .440 CorBon in a DEP. No problems at all.

It does seem prudent to suspect the pistol, rather than the round's design, when the round is proven to perform well in other pistols...
 
I got a conversion barrel in 357 Sig for my G27 and it fed reliably and I enjoyed shooting it. I did have one problem no one else mentions and that was, with the bottle neck configuration, I had trouble loading the last couple of rounds in the magazine. When I pressed the next round down, the top round in the mag "nose dived" and I had problems loading the mags to capacity without using the loading tool. Anyone else experience this?
I do have some doubts that round will do anything the better rounds of 40 S&W won't do as well. It was an interesting experiment, though.

------------------
OJ
NRA LIFE MEMBER
 
Status
Not open for further replies.
Back
Top