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Posted: 2/10/2012 10:48:25 AM EDT
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Hope this hasn't been covered already. I'm at lunch and limited on time for searching topics.
Recently purchased a few P-Mags and really like them except that when the first round is stripped by the BCG and loaded into the chamber, if the round is not fired and I pull on the charging handle to unload the rifle it is jammed in there hard. Have to bump the butt on a hard surface while pulling the charging handle down to get it out. Now, allow me to answer ahead of time some of the questions you may be ready to ask. Reloads. Yes. Mine. Same loads I have used for several years during Highpower competition and general plinking. Two different rifles. Both do NOT have M4 feed ramps. (I'm suspecting this may the reason). Do not have this issue at all with USGI type mags and same rounds. So, I'm suspecting that because the follower in the PMags is more centered it's causing the issue? Or is there something else? Thanks in advance for your help. |
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I'm having trouble reconciling the problem and the magazine. You're saying the round is sticking in the chamber, right? What does that have to do with the magazine? It's already left the magazine when it's chambered, and the poor magazine is just sitting there waiting to feed another round.
Okay, unless the BCG is somehow hanging up on the next round in the magazine or the feed lips, and the round isn't really sticking in the chamber, it isn't the magazine. Is it possible the whole BCG is hanging up, and not just the cartridge in the chamber? If so, try dropping the magazine and relieving any tension on the underside of the BCG and see if that changes things. (EDIT - Okay, I see you are already dropping the mag first. I reiterate my opinion the magazine ain't causing the round to stick in the chamber, regardless whether this happens with USGI mags or not. If it turns out that it IS, by all means let us know how that's happening!) . . |
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What does the brass look like when you pull it from the chamber? Any markings? What happens if you take the ejected round and load it into a USGI mag and then chamber it? Any problems extracting then?
The only thing that I could figure (and this would be confirmed by the last test I suggested) is that the brass is being damaged when it is chambered. Maybe something to do with the feed angle from the P-Mag or your chamber, or some combonation of the two. |
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I'm having trouble reconciling the problem and the magazine. You're saying the round is sticking in the chamber, right? What does that have to do with the magazine? It's already left the magazine when it's chambered, and the poor magazine is just sitting there waiting to feed another round. . You're right. I didn't read carefully enough. He also said unfired reload, I believe. The first thing I'd do is to try a factory round. If it worked, then I would know that I'm not resizing properly. |
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Maybe I'm missing something, but if your dropping the mag before unloading it, how else could it have anything to do with it any more than damaging the round when loading it? I know that my pmags can be loaded really tight to 31 rounds and I can see that being an issue.
Any pics of the round after unloading it? I would expect to see it dented and scratched pretty bad since normally once it's loaded, it's loaded. |
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I'll try to hit all of the responses here.
"I'm having trouble reconciling the problem and the magazine. You're saying the round is sticking in the chamber, right? What does that have to do with the magazine?" I believe it is the angle that it is being fed into the chamber. (at this time). "What does the brass look like when you pull it from the chamber? Any markings? What happens if you take the ejected round and load it into a USGI mag and then chamber it? Any problems extracting then?" There are scratches on the pill. And Small scratches on the case near the shoulder. I do not have any pics at this time. No problems when loading into GI mag and dropping BCG. "The first thing I'd do is to try a factory round. If it worked, then I would know that I'm not resizing properly" These are reloads which makes them all suspect, partucularly to those that do not reload. No Offense, but I have been reloading a long time. U se a case gauge, measure cases, trim cases etc. These loads are essentially match grade ammo in all aspects. The same loads I have used across the course for Highpower competition.. "are your uppers m4 feedramps and not your barrels or something?" Already stated, neither rifle has M4 ramps, barrel etc. "Are you leting the charging handle fly when loading it or are you riding it closed slowly?" Dropping the BCG via the release. I typically don't yank the charging handle to drop the bolt. there"It's your reloads." I wish you were right. However, in this case, see above statements. All responses are appreciated. 10 heads are better than one. That's why I came here. To see if anyone has had the same experience. This has never been an issue until I started using the P-Mags, hence, that is why I see them as suspect. Not that there is anything wrong with them, but if you consider they are "relatively" knew in design and manufacture and there have been some changes to the AR platform in recent years there could be a correlation. Both my rifles are as stated Pre-M4 style. One is a National Match RRA upper on a Bushy lower which is a tack driver out to 600 yards. The other is a mid-length carbine based on an Ameetec lower with an upper (I think) from M&A? Not a great rifle but has no history of issues with GI mags. I'm getting the same results from both rifles with P-Mags. Thanks and let's keep working on this. |
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If the round is actually fully seated in the chamber, it doesn't matter how it was fed unless the PMag is causing some odd damage to the round that is enough to not let it extract easily, but still allow it to chamber.
Do you have a rifle upper receiver with a carbine barrel extension? That can cause the rounds to bend since they jump into the chamber and bounce off the top. Pics of your upper? Also, who made your rifle or carbine? Is the action spring "upgraded" with a more powerful spring that could still feed a damaged round? |
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...if the round is not fired and I pull on the charging handle to unload the rifle it is jammed in there hard. Two different rifles. I wouldn't implicate magazines or feed ramps. A stuck round screams of a resizing problem or a chamber problem. Change bullet mfrs, different ogive ? Can you determine what part of the cartridge is hanging up ? Marks ? Two different rifles.....two different chambers. The plot thickens. Throw down for a box of factory rounds and do the test. DD Been handloading since 1971. |
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I believe this goes in reloading... did you check the brass for proper drop in and seat and eject BEFORE you put powder and a bullet in it? I'd bet anything the resizing die isn't shrinking the base enough... and you just need to adjust your die.
Your reloads should drop in from your fingers, seat, allow you to slowly close the BCG and then pull the charging handle to eject round... all with very little effort. Again, do this with your brass only before you add bullet and powder.. then at a safe place like the range, test your reloaded rounds too. If it takes anything more than just a light touch, something is wrong with your reloading setup. Just because your reloads work in one rifle doens't mean another.. it could have a tighter chamber... |
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Your lower is out of spec And, we're off!......... 
LOL Probably. I would first double check and make sure 31 rounds are not loaded. Then check function by changing out parts. Magazine, Lower, Ammo etc. you will then see what is the culprit. If it is the mag give our tech support a call and they will take it from there. |
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