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All suspect CCI SPPM 9mm loads were <130pf, many ~125pf. Almost all 9mm brass was once fired (i.e. reloaded for the first time). I have >30k of 9mm brass and a system to cycle it. Regardless, I can't see 125-130pf 9mm loads wearing out brass after one loading. And, the .45acp small primer brass was once fired for sure. Can't get much better than that for non-new reloading brass. I'm sticking to my belief of too low pressure not deforming the harder CCI SPPM primer enough to seal the pocket. The data supports that. I changed nothing in my test of SPPM other than increasing to >140pf and the gas cutting stopped. And, I think the SPPM gas cutting in the much lower pressure .45acp lends added support to my too low pressure theory. YMMV, but I have my answer. p.s. As a reminder, my 30k of CCI SPPM were the older red box variety. New CCI SPPM, and other brand SPPM, may vary.

I burned 8# of TG in 9mm lead. It worked, but I found it to be nothing special at day's end. And, I'm not running LRN in 9mm for now.

As noted, my experience relates only to ~20k of CCI SPPM w/ Unique and Titegroup in 9mm using mixed brass and >1k w/ Bullseye w/ .45acp using Blazer small primer brass. As noted, powder burn rate did not matter. My opinion based on my experience is that it's due to too low pressure (>130pf, and well under at that) in 9mm and too low pressure in .45acp regardless. I only run SPP now, but would likely be fine runnning SPPM >140fp in 9mm if that's all I had. p.s. I will not run .45acp in SPPM again because I don't think the pressure can safely get high enough to cause primer flow that will reliably seal the primer pocket.

Loads near and under 130pf w/ CCI SPPM resulted in gas cutting for me. And, as show in the photos, the low pressure rounds show very little if any primer flow. However, it's a bit easier to see primer flow in a Glock because of the large striker opening. The 4.7gr Unique noted above resulted in clear primer flow, but I'm running 4.9gr (~1150fps) for a bit added insurance with the last CCI SPPM I have. The question I have is whether the 147gr @ 925fps (~136pf) loads show enough primer flow. If not, it could be an issue. If so, he should be okay. But, I don't have experience with Rem or Fed SPPM. What's the velocity on those? If you are getting primer deformation pressure is likely high enough to deform the primer enough to completely seal the pocket. Loads I ran in high volume w/ CCI SPPM (that gas cut) were ~1000-1050fps w/ 124gr FMJ/Plated resulting in a 130pf or under. These were weak loads. My SPPM loads in this test were ~1150fps (>140pf) and have not show issues, but I can't run these in high volume with CCI SPPM to be certain because I traded my remaining 9k for SPP. CCI are harder. That's been my experience as well. These CCI SPPM are the only primers I've ever had repeated light primer strikes with in Glocks.

Not sure, but you should be okay as that is not a real weak load like I ran. Also, yours are Rem SPPM and mine were CCI. I can tell you the loads that gas cut for me where using older red box CCI SPPM running under 130pf, many well under. As noted above, primer flow (i.e. deformation that will seal the primer pocket) exists running about 140pf, and I'm running everything at least that now with the last bit of CCI SPPM I have. I can't speak from experience for loads around 135pf w/ CCI SPPM because I did not run them in the test process noted here.

Bullseye. I keep it old school. Runs very well for me.

If you are running 1k or more a month in 9mm consider the Dillon 550 or SDB. I run a dedicated pair of Square Deals in 9mm and .45acp. I believe the SDB to be the best value in mid-volume handgun loading. I run about 1k in 9mm and about 250 in .45acp monthly. I'm pleased with the press and Dillon's customer service is amazing.

I settled on 1.135" w/ 124gr FMJ.

I have run SPP, SPPM, SRP and SRPM in 9mm. And, in a variety of brands run interchangeably. Overall, not much changed, but the SPP loads seemed most consistent.

I liked Solo 1000 because it was low smoke for lead. Not my first choice for much else. I've moved on.

This. And, OAL does matter. If memory serves, TG @ 3.7gr @ 1.135" would barely cycle my Glock 26, though I could get 3.4gr to dribble out of a Glock 17. I go with 4.0-4.1gr.

I can confirm the above when used in weak 9mm loads, as well as SPP .45acp, from experience (as linked above)

Final Update: I ran matching loads in CCI SPP and CCI SPPM. The SPPM are harder. My testing puts this to bed for me and conclusively proves that harder SPPM, SRP and SRPM can cause breech cutting around the primer cup using weak loads because the primer does not deform to seal the primer pocket. Picture of SPPM vs. SPP: These two cases are representative of loads fired. I've since traded all my SPPM for SPP. The SPP indent and primer flow is more pronounced, and it's much more noticeable in real life.

I've reloaded them changing nothing. Worked the same as LPP. I just keep collecting them for a day I have only SPP on hand. That's day has yet to come though.

Yes, the best. I have a handle on the way for my (>35k) 9mm SDB to replace the broken one, and the new style brass bushings to replace the older/worn plastic ones on my (~10k) .45acp SDB. Both my SDBs are original (i.e. old school), and all the parts that have broken over the years have been redesigned to be more robust.

The SP01 is a great, great range blaster and gamer. I view the CZ like a Ferrari; definately a higher performance tool. I shot my SP01 Custom and 75 Compact better than my Glocks, and about as well as the 1911. The CZ SP01 Custom was the finest 9mm I ever owned/shot and a single action trigger has a lot to do with it, as does the grip angle and balance. The heft of the SP01, especially with the rail up front, really helps tame recoil, and the 75 Compact is a heavy gun as well. Sold both because I decided I shoot Glocks (and the 1911) well enough, wanted to limit my platforms, I have smaller CCWs and did not need a range/game only blaster. It was the right choice for me. If you get a SP01 be sure you can make weight for IPDA if that's your thing. Bottom-line is that the CZ is a great shooting gun.

I run all range pickups. I dump all tumbled brass into buckets. I start with one bucket, empty it, then move to the next. Brass goes into the empty bucket and the process repeats. I add buckets as needed. The more brass I get the longer the duration between loadings. I figure I've loaded some brass 3-4 times and it's fine. And, I've had splits case mouths, too. I just toss any brass that does not look/feel right.

I've run lots of SPPM, and less than 1k of SRP and/or SRPM in 9mm. The rifle primers, especially the SRPM, definately made more flash come out the barrel. I could not tell much difference in the load performance, and I did not change load data, but the rifle primers did seem to have slightly more oomph. I did/do get a few light primer strikes in Glocks, but more an issue is that running weak loads w/ SPPM caused THIS, and I venture to guess the issue would be made worse with even harder rifle primes. If you run them hot in a hammer-fired gun you should be fine.

I've used SPP in .45acp brass without changing anything. Worked fine.

Unique. IMO the "Unique is too dirty" commments are way overblown, and Unique is a very forgiving, very versatile powder with tons of load data available. Also, any of the other mid-burners will be fine, too.

I can tell you SPPM gas cutting in low pressure 9mm loads is not "well known" in many circles definatively. SRP and SRPM, maybe, but not SPPM. I've heard/had many suggested causes, including from many long-time reloaders (heck, I'm 15+ years myself), that the cause was bad primers, stretched brass pocket, bad brass, over-pressure, hard primers, user error, fast powder, and more. I eliminated all the other possibilities and was left with only too hard primers in too low pressure loads. To have the definative cause be too hard SPPM primers in too weak loads was news to me, and will be to many. Now, I know. I agree it's not "well known" that SPPM can gas cut in too low pressure loads. Very helpful links. Thanks. One load I ran in volume was a 124gr FMJ 3.9-4.0gr TG load. Update: I ran the 4.9gr Unique load today and primer flow and indent depth appears identical to the 4.7gr load. So, >4.7gr provides enough pressure for primer flow that should seal the pocket. Also, I just swapped 4k SPPM with SPP at the local gun show. The guy will trade my remaining 5k SPPM next show. So, that will be the end of it. If I'd have known SPPM and low pressure loads was the cause sooner I'd had swapped them already.

I have a Gen3 Glock 17 and a former Gen2 Glock 19 I've run lots of (old red box CCI) SPPM though. My current Gen3 Glock 17 has about 7-8k through it (maybe more) and the Gen2 Glock 19 had >20k. About 2/3 of these have been these SPPM because I bought about 30k in FTF deals for $10-$20k back in the crazy price days. And, I've run a few hundred SRP and SRPM as well. Loads have cycled fine with no change in accuracy. And, I do not change my powder charge. I've always known all these 124gr FMJ/Plated SPPM loads are well under-pressure as the bulk have run only 1000-1050fps, or even less for some LRN loads used in the Glock 19 w/ LWD and KKM barrels. Breech face gas cutting has occured (consistent with the primer cup), and has for some time in this Glock 17, and it was the same in the G19. I've also run these loads in other guns with similar results (e.g. slight breech face marks), though the ring has not formed due to lower volume shooting. I've even run them in once-fired, sorted .45acp brass (with a hammer-fired 1911: Unique 3.9-4.0gr w/ 200gr LSWC @ 1.135", which is a tame load) to rule out over-pressure, flash hole difference, primer impact deformation, stretched primer pocker (e.g. brass issues), etc. (same result). It does not seem to matter if I use a faster or slower powder, with mixed brass or not, nor does it seem to matter using once-fired brass or more-fired. I have not observed damage to primers, fired primers remain seated (i.e. are not loose), and new primers seat fine in fired brass (i.e. smooth, with slight resistance and seat fully) using two different Dillon SD progressives. So, becoming more curious only recently, I've narrowed my theory of late, and do not think brass is the culprit. I believe the harder primer cup is not expanding to allow a tight primer pocket seal at the lower handgun pressures, 9mm or .45acp. Meaning, not over-pressure or a streched primer pocket, but under-pressure (weak) loads with these harder older red box CCI SPPM primers. I do think higher 9mm pressure (vs. .45acp) exacerbates it, but the 9mm pressure, at least the weak 1000-1050fps loads I've run, is still below the pressures needed to seal these SPPM in the primer pocket, meaning more gas escapes. And, since most of the cutting in my 9mm is from (older red box CCI) SPPM, the hardness of the cup must be more like rifle primers. I've heard/read, and have experienced myself via light primer strikes, that these CCI SPPM are harder than current production and much more like rifle primers. So, none of this may matter if you don't have those, but could be applicable if you plan to run SRP/SRPM (i.e. harder cup primers) in 9mm. If I push the 9mm faster, to +p or +p+, it may go away or lessen, and I'm testing that now running all loads at ~1150fps. I have already noticed differences in primer flow patterns (see image below). But, I can't push .45acp fast enough if low pressure is the cause. Regarding primer hardness this picture of primers shows differences in indent depth and primer flow into Glock striker hole. As is often the case, the picture is not as clear as real life. These examples are representative of the lot: Top (blue marker) = Older Red Box CCI SPPM w/ 4.7gr Unique (some primer flow, shallow indent) Second Row (red marker) = Older Red Box CCI SPPM w/ 4.2gr Unique (little/no primer flow, shallow indent) Third Row (cleaned/tumbled) = Range Brass (clear primer flow, deeper indent) Bottom (cleaned/tumbled) = SPP w/ 4.2gr Unique (clear primer flow, deeper indent) (Note: A Berry's 124gr FP w/ 4.9gr Unique @1.030" ran ~1150fps for me and 5.2gr ~1210fps, so the 4.7gr load pictured is below 1150fps.) Update 2/19/12: I ran the 4.9gr Unique load and primer flow and indent depth appears identical to the 4.7gr load. So, >4.7gr provides enough pressure for primer flow that should seal the pocket. Also, I just swapped 4k SPPM with SPP at the local gun show. The guy will trade my remaining 5k SPPM next show. So, that will be the end of it. If I'd have known SPPM and low pressure loads was the cause sooner I'd had swapped them already. I've pretty much always run weak to mid-level loads. All along, and for many years, I thought the issue was using mixed brass and I did not want to sort. That, and I did not really care since I knew the loads were safe. But, I'm beginning to think conclusively that too weak loads using harder primers is the issue. More rounds downrange with hotter loads will prove or disprove that theory. I view Glocks as tools, and I consider Glocks "throwaway" guns somewhat anyway. I consider this cosmentic for now, and will monitor to see if breech integrity could become compromised if ring gets deeper. Obviously, this does not matter to me in this Glock 17 (and did not matter in my former Glock 19) as I keep running SPPM, even SRP and SRPM. But, I don't use SPPM, SRP or SRPM in any volume in my other 9mms due to this, nor would I run them in any 9mm I really cared about, and stick with using SPP instead for now. Even if the issue goes away, it may be just these older red box CCI primers, but I won't know that for sure as I've not run other SPPM in high volume. Regardless, I often share SPPM, even SRP and SRPM run fine in 9mm. And, they do. I figured I'd share this as a PSA to let folks know your breech may show accelated wear using SPPM, SRP or SRPM if you run weak loads. To me, though I'll bump up the load to see if it goes away, it's worth it given what I paid for these primers and how cheap Glocks are since I've saved more than enough to buy the gun again.

I don't like TG with lead bullets, but have found that 4.4gr/Bullseye gave me 770.4fps and is a good shooter. Same here. I've run TG w/ 230gr, but run 3.9-4.2gr of BE now.

Standard primer for standard loads is recommended. That said, I run magnum primers in standard loads (LPP and SPP) all the time. I run what I get cheapest and in have never had issues running light-medium loads (I don't load anything hot). YMMV.

I have to run a 230gr LRN at/under 1.235 for a LWD barrel in a Glock 30. I'll run them down to 1.225 which is right at the driving band.