I've had a M&P 9mm for awhile. A friend recently bought one. I took him to the range and after a couple boxes of factory rounds I offered him some of my reloads as he was out of ammo. His started failing to lockup with two different versions of my reloads. We disassembled our pistols and his barrel chamber is a lot tighter tolerance than mine. All loads dropped right into mine but only factory rounds would drop into his and headspace correctly? Are the newer guns all coming out this way to discourage using reloaded ammo? I've been reloading for almost 30 years and do know how to use case gauges. Any thoughts???
Tight chambers on newer M&P 9mm's ?
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I've had a M&P 9mm for awhile. A friend recently bought one. I took him to the range and after a couple boxes of factory rounds I offered him some of my reloads as he was out of ammo. His started failing to lockup with two different versions of my reloads. We disassembled our pistols and his barrel chamber is a lot tighter tolerance than mine. All loads dropped right into mine but only factory rounds would drop into his and headspace correctly? Are the newer guns all coming out this way to discourage using reloaded ammo? I've been reloading for almost 30 years and do know how to use case gauges. Any thoughts???
Spotteddog
Member
I hardly think that if "factory" loads chambered, fired, ejected and fed, I'd much question the new gun? I might be tempted to use a gauge on your chamber, however?
dennis40x
US Veteran
If there were no problems with chambering new commercial ammunition then I believe your reloaded ammunition may be the issue. This is not to say that your friends MP9 could not have a dimensionally tighter barrel chamber. That particular barrels chamber may be tighter/smaller but be within manufacturing tolerance. I would believe that as part of their (S&W) quality control procedure the tooling is inspected for wear and tolerance range acceptability.
handgunner356
Member
I use to reload without gauging my ammo, but one day out with serveral officers one ran out of ammo. I gave him a box of my reloads and he started having problems, second box same thing. Five 6906s', all close in serial number, all the others fired the ammo that wouldn't work in his. Going back and gauging all my loaded 9mm ammo almost 20% wouldn't drop into the gauge but yet worked in all my guns. Ran into the same thing with two M&P40c less than 100 serial numbers off, the one was a much tighter chamber than the other, and it didn't like Wolf ammo at all.
I ran several of my two different loads of my reloads through a case gauge again today. A few rounds did need "the mild push" to headspace all the way. What his pistol was doing on some rounds was locking up the pistol out of battery and you would have to push the slide back on the edge of the bench as you couldn't clear it by hand. The only factory rounds we had that day were white box USA 115 FMJ. He's going to bring it over and we'll take some further measurements. He doesn't shoot much and will probably only shoot factory but that didn't leave a real good feeling of dependability in his mind on his new pistol.
Thanks for the replies to my first post also.
Thanks for the replies to my first post also.
Spotteddog
Member
If he thinks he needs to be really paranoiac about it, tell him to tear down the pistol and test fit the factory S/D loads he wants to run into his chamber. But, it's always a better idea to try S/D loads to make SURE they run in the real world?
deputydog
Member
I am not sure on the pistols for reloading tolorance from gun to gun , even the same make and model,but I can say I no on rifles a .223 shot from my Bushmaster, reloaded, and loaded to my brothers Bushmaster will fail to chamber and all are very tight if they do. My reloads will chamber eveytime in my gun though . I have found this to be the case with most all my varmint rifles they will shoot my reloads, formed from my chamber perfect,but not someone elses from ther chamber.
I was a reloader for many years when I was younger. I saw my fair share of reloaded ammunition (my own and as made by other folks) which was slightly out-of-spec when it came to OAL, or the cases hadn't been exactly sized back down to 'new' dimensions, or the taper crimp wasn't exactly right, or the case rims had become worn, dented or gouged so that they didn't seat normally under the extractor (and hence allow normal loading/chambering), etc., etc..
Or, as S&W states it (partially) in their manual, "RELOADED OR HANDLOADED AMMUNITION, MAY HAVE MANY MANUFACTURING AND QUALITY VARIABLES ..."
I've experienced and observed more issues with reloaded ammunition not functioning in service weapons than with factory-new ammunition, too.
I lost track of the times I heard someone in a class using reloaded ammunition, and who experienced a feeding failure, act baffled when a reloaded round wouldn't allow for normal chambering in their pistol. Usually it was, "I've never had that happen", or "My friend's reloaded ammunition has always worked in my gun before today" ... but there we were, standing there with a pistol which wouldn't feed one or more rounds during shot strings, and often with a case (or a few) exhibiting signs of having been reloaded an unknown number of times.
I remember when I was in an armorer class a while back and someone asked about how many times a round could be chambered. The instructor told the class of a study where another major firearms manufacturer had asked this same question of the major ammunition companies. The answer? It seems the major ammunition manufacturers only intended for their new production ammunition to remain within normal specification and tolerance when chambered ONCE. That's certainly a safe, conservative standpoint from which to look at the question, isn't it?
Oh yeah, I was told a while back that the newer CNC equipment in which S&W has been heavily investing constantly checks itself for many things, including the sharpness of the cutting tools. If the computer senses a cutting tool in which the sharpness falls below the desired programmed specifications the equipment shuts itself down until the cutter can be replaced and the equipment restarted by an operator. Aren't computers handy? (When they work as intended and desired, of course.
) )
I remember when we sometimes used to have to correct a tight/high spot in older pistol chambers upon occasion (among the occasional early 3rd gen pistols, for example, or a 1911 barrel). Nice not to have to do that nowadays. Using a finishing reamer improperly can allow for a barrel to be ruined pretty easily and quickly by someone not experienced in the proper use of the tools.
As long as good quality factory ammunition properly feeds, chambers, fires, extracts & ejects in my pistols I don't worry about reloaded ammunition. The M&P works normally with factory ammunition, right?
Now, what constitutes 'good quality' ammunition can create some disagreement among some folks time to time ... and even new factory fresh ammunition can have its occasional hiccup every once in a while.
Worried about making sure even new factory ammunition will feed & chamber in a high quality firearm, like maybe a Sig Sauer pistol? Take a look at Page 10 of the Sig Sauer Preventive Maintenance Guide, where it offers this recommendation for 'service/street ammunition' in order to avoid some potential ammunition-related problems ...
http://www.sigsauer.com/CustomerService/documents/PREVENTMAINTGUIDE.pdf
Can't be too careful, perhaps?
Or, as S&W states it (partially) in their manual, "RELOADED OR HANDLOADED AMMUNITION, MAY HAVE MANY MANUFACTURING AND QUALITY VARIABLES ..."
I've experienced and observed more issues with reloaded ammunition not functioning in service weapons than with factory-new ammunition, too.
I lost track of the times I heard someone in a class using reloaded ammunition, and who experienced a feeding failure, act baffled when a reloaded round wouldn't allow for normal chambering in their pistol. Usually it was, "I've never had that happen", or "My friend's reloaded ammunition has always worked in my gun before today" ... but there we were, standing there with a pistol which wouldn't feed one or more rounds during shot strings, and often with a case (or a few) exhibiting signs of having been reloaded an unknown number of times.
I remember when I was in an armorer class a while back and someone asked about how many times a round could be chambered. The instructor told the class of a study where another major firearms manufacturer had asked this same question of the major ammunition companies. The answer? It seems the major ammunition manufacturers only intended for their new production ammunition to remain within normal specification and tolerance when chambered ONCE. That's certainly a safe, conservative standpoint from which to look at the question, isn't it?
Oh yeah, I was told a while back that the newer CNC equipment in which S&W has been heavily investing constantly checks itself for many things, including the sharpness of the cutting tools. If the computer senses a cutting tool in which the sharpness falls below the desired programmed specifications the equipment shuts itself down until the cutter can be replaced and the equipment restarted by an operator. Aren't computers handy? (When they work as intended and desired, of course.
I remember when we sometimes used to have to correct a tight/high spot in older pistol chambers upon occasion (among the occasional early 3rd gen pistols, for example, or a 1911 barrel). Nice not to have to do that nowadays. Using a finishing reamer improperly can allow for a barrel to be ruined pretty easily and quickly by someone not experienced in the proper use of the tools.
As long as good quality factory ammunition properly feeds, chambers, fires, extracts & ejects in my pistols I don't worry about reloaded ammunition. The M&P works normally with factory ammunition, right?
Now, what constitutes 'good quality' ammunition can create some disagreement among some folks time to time ... and even new factory fresh ammunition can have its occasional hiccup every once in a while.
Worried about making sure even new factory ammunition will feed & chamber in a high quality firearm, like maybe a Sig Sauer pistol? Take a look at Page 10 of the Sig Sauer Preventive Maintenance Guide, where it offers this recommendation for 'service/street ammunition' in order to avoid some potential ammunition-related problems ...
http://www.sigsauer.com/CustomerService/documents/PREVENTMAINTGUIDE.pdf
Can't be too careful, perhaps?
^^ Well written Fastbolt with valid points.
The reloads mentioned were all cast lead, not jacketed. Of the new shooter and gun, it's the second pistol he's ever owned and he hasn't been shooting in a couple of years. He will never reload, probably never compete, and the gun will be for home defense that is hopefully never needed. I will still look at his chamber in the future to verify dimensions are correct.
I have an early Kahr pistol that has a tight chamber, factory addressed problem, that won't feed some brands of factory ammo.
Edit: Kahr won't feed, as in certain bullet configurations won't allow the round to headspace account short throat on the bore. The bullet is actually shoved into the case to allow lockup creating a pressure problem I'm sure.
The reloads mentioned were all cast lead, not jacketed. Of the new shooter and gun, it's the second pistol he's ever owned and he hasn't been shooting in a couple of years. He will never reload, probably never compete, and the gun will be for home defense that is hopefully never needed. I will still look at his chamber in the future to verify dimensions are correct.
I have an early Kahr pistol that has a tight chamber, factory addressed problem, that won't feed some brands of factory ammo.
Edit: Kahr won't feed, as in certain bullet configurations won't allow the round to headspace account short throat on the bore. The bullet is actually shoved into the case to allow lockup creating a pressure problem I'm sure.
JoeS
Member
I've always found the 9mm to be a bit trickier than some rounds to load due to the taper of the case and the oversize bores often encountered on European 9mms. I find this particularly true with cast lead slugs.
I used to do a lot of lead bullets through Browning Hi-Powers and found that for decent accuracy you needed a .357 bullet. This would often give a slight bulge in the case which was not a problem in a Browning which generally do not have tight chambers.
I also am doubtful about commercial dies on this round. It seems to me like they almost need a final die to smooth out that bit of bulge. I've often thought I would like to see how its done in an ammo factory just out of curiousity.
I'm wondering if your cast bullets are sized .356 or larger? It could be that if they are it creates just enough of a bulge in the case to hang up his pistol. Its certainly possible that his has a slightly tighter chamber. Another question might be if the chamber was correctly polished from the factory, I ran into this with a Sig 220 once.
There is probably nothing wrong with your ammo at all, rather it probably puts just enough of a dimensional variant in there to show up as a malfunction on his pistol.
I used to do a lot of lead bullets through Browning Hi-Powers and found that for decent accuracy you needed a .357 bullet. This would often give a slight bulge in the case which was not a problem in a Browning which generally do not have tight chambers.
I also am doubtful about commercial dies on this round. It seems to me like they almost need a final die to smooth out that bit of bulge. I've often thought I would like to see how its done in an ammo factory just out of curiousity.
I'm wondering if your cast bullets are sized .356 or larger? It could be that if they are it creates just enough of a bulge in the case to hang up his pistol. Its certainly possible that his has a slightly tighter chamber. Another question might be if the chamber was correctly polished from the factory, I ran into this with a Sig 220 once.
There is probably nothing wrong with your ammo at all, rather it probably puts just enough of a dimensional variant in there to show up as a malfunction on his pistol.
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