shoresroad

Ok, here are the measurements I've got on my stock, MCarbo, and Tandemkross recoil buffers. Both the MCarbo and Tandemkross rubber buffers have some variation in their thickness, I'm guessing due to slight variation in their rubber molding process. The hard vinyl stock Ruger recoil buffer appears to be uniform in thickness... MCarbo "Shock Buffer" thickness: 0.318 to 0.324 inches Tandemkross "Shock Block" thickness: 0.304 to 0.310 inches Ruger stock recoil buffer: 0.244 inches So, the Ruger recoil buffer is definitely thinner than either of the other two buffers. Interestingly, I also found this statement on the Volquartsen website page for their discontinued Target Hammer... "This part is not compatible with aftermarket recoil buffers" Target Hammer for Ruger PC Carbine | Volquartsen Firearms That statement does not appear in the listing for the Volquartsen Ruger PC Carbine Target Hammer on eBay. But I still would have bought it to experiment with... Volquartsen Target Hammer Kit Ruger PC Carbine Charger Takedown VF9TH 810162019518 | eBay So, the one change I'm going to make is to reinstall the Ruger stock recoil buffer allowing for the slightly longer bolt travel to see if that will eliminate the burst fire/trigger reset problem with the hot Winchester Ranger 127 grain +P+ RA9TA. Will report back in a week or two after I get down to the range to try out the new configuration. P.S. I also have one more variable in the equation. In anticipation of the hot Winchester Ranger ammo, I'm also running the Tandemkross 20% added power recoil spring. I'm going to leave it in for now.

@jrdoran Sorry to necro this post, but there is very little information on the topic of trigger mods for the Ruger PC Carbine, and most of them are at least a couple of years old. Thanks for your "Solved" post above. I have been having problems with burst fire and/or my trigger not resetting after installing the MCarbo shock buffer and the Volquartsen Target Hammer (which has been discontinued by Volquartsen but is still available "new" on eBay from a Volquartsen dealer). The Volquartsen Target Hammer kit reduced the trigger pull on my new Ruger Magpul PC Carbine from 5.5 lbs to 3.5 lbs, which is where I want it. And on the first 200 rounds of PF130 I had no problems. But this is going to be a home defense rifle, and when I moved up to Winchester Ranger 127 grain +P+ RA9TA to sight in my red dot, here came the burst fire/trigger reset problems. So same problem, but at a higher PF threshold. So, after reading your post, I'm going to start by removing the MCarbo shock buffer. I also have a Tandemkross Shock Block that I'm going to measure. If it is thicker than the stock shock buffer, then I'll stick with the stock shock buffer and see how things go. Thanks for your information. I'm sure that others will continue to find it helpful in the future.

Mystery solved. After pulling these out again and amusing the guys at a match about a week ago one of them who is also a gunsmith and M&P Armorer took one home and took it apart. Deformed bullet. At the crimp the bullet measured .355 At the base the bullet measured .355 But the rest of the body of the bullet was concave and measured much less. So only about 10% of the surface that would normally touch the rifling was making contact. His guess was that the bullets were slipping down the barrel with almost no rotation and coming out like a knuckle ball. He pulled out his SVI open gun with optics and couldn't hit an 8" plate at 10 yards with them. We named them bottle rockets, as that's how they flew...lol Every 4th or 5th bullet would fly true, but that is as good as it got. If I had bought this case more recently I would have sent them back, but now I can't even remember where I got them. Oh well

Well, it was the Armscor ammo. I had a chance to get out and shoot groups from a rest today with Corbon 115 +P DPX, Federal 124 +P HST, Geco 124 FMJ, and Magtech 124 FMJ with all groups being 1.75 inches or better at 15 yards. My best group was 7/8" with the Magtech (which is as good as I can shoot). Then I pulled out the Armscor 124 grain FMJ again and shot a 20 inch group from the same rest with 3 bullets keyholing...lol So now I'm totally happy with my M&P 9 Pro. I know I sounded like an idiot, but I've just never run into truly bad ammo like this before. A lone round (which I would have blamed on myself), but never everything coming out of a couple of boxes from the case I had cracked open. I'm still unpacking from a recent move and haven't found my bullet puller yet, but when I do I'll pull a couple of bullets from the Armscor and put a mic on them. Undersized bullets are the only thing I can think of that would cause this, but I'm no expert. Anyway, I'll post here again once I get a measurement. If its not bullet size then I'll never know why, but I could throw rocks at the target more accurately than I can shoot this Armscor stuff. I forgot to bring another 9mm pistol and no other shooters that I knew at the range today but I'll also be using up this Armscor with other pistols just to see and also amuse myself. Thanks!

Ok, after sleeping on it and some internet research I've realized this has got to be the Armscor ammo. I just found a thread where Front Sight sent back multiple cases of Armscor 124 grain FMJ due to keyholing (in addition to several individuals who said they were having the same problem with it). This was back in 2012 and that was about when I bought this case (even though I just cracked it open). Wasn't able to shoot this past weekend but will be heading down to the range sometime this week with different ammo including some premium stuff that I know for sure should be in spec. Will give you an update but after thinking about it I'm pretty sure this has to be a case of undersized bullets or something along those lines that just happened to coincide with my new gun. It was like I was shooting knuckleballs the other day and undersized bullets would explain it. Appreciate the input, guys!

Ok, thanks Nick. I'd heard there were accuracy problems with the 9 Pro at some point, but of course I didn't expect anything like this.

"what is the build date on you gun?" 3/5/2015 I've got a 4" M&P .45 that is dead nuts accurate so I felt confident buying this 9 Pro. Its a new case of Armscor that I haven't shot through any other guns yet, so I'm hoping its the problem. I've just never run into persistent keyholing before other than the odd round every once in a blue moon or the odd round you see at a match when pasting targets.

Hi guys, Need some help here. I've always shot 1911's in IDPA (CDP and ESP). But also own quite a few polymer guns and have always shot them well. Decided to get an SSP pistol this year so went with a brand new M&P 9 Pro. Added a Dawson adjustable sight set, but all else still stock. Took it to the range for the first time yesterday to dial in my sights and it shot like a shotgun from a rest at 15 yards. Approximately 1/3 of the bullets keyholed on the target (big time rectangles...no doubt). I was using factory Armscor 124 grain FMJ ammo. Never had keyholing before, let alone a gun that wouldn't group like this (first shot 10 inches high to the right, second shot 8 inches low to the left...it was ridiculous). I can normally shoot a two inch or better group at 15 yards from a rest (best my eyes can do). Group size for this gun was the IDPA target, which isn't a group. It really did look like a #1 buckshot shotgun pattern from an 18" cylinder choke after the first 15 rounds. Where do I start? Is it maybe the ammo? The barrel? Will try different ammo next time but also wanted to ask. Thanks, and I'll also search for prior articles, but I'm seeing comments on the net about design changes over the years to the M&P 9 Pro, so wondering what the current state of affairs is with this model. I had hoped to shoot this gun in SSP, so I don't think changing the barrel to other than stock is an option.

I thought it was just the opposite. IDPA has the XDM in the ESP class and the PPQ in SSP.

Be careful with the P250 holsters. I've got a Bladetech P250 compact holster and my new P320 compact won't fit at all...its too tall (combined slide/dust cover dimensions). Thinking about it, it has to be the slide height as the grip modules are the same.

Hey Guys, Got "spot on" load data from members here when I started reloading 45 ACP for the first time a few years ago...Thanks! Now I'll be reloading 9mm to meet IDPA Power Factor 125,000 with the following components: Barry's Plated 124gr RN over TiteGroup (already have both). Any ideas for COL and Charge Weight would be great. Thanks in advance!

Thanks for everyone's feedback. Sounds like I need to add Rich at Canyon Creek to my list. Seems like I'm on the right track so will get on the phone and talk to a few of these folks before I decide. This will by my first "polymer" trigger job so wasn't sure where to start.

Hello everyone, Ok, looking for opinions here. I want to have a trigger job done on my XDM 5.25 9mm and it looks like my best options are Springer Precision, Powder River Precision, or Springfield Custom Shop. In the Leatham video where he introduces the 5.25 he says his trigger was done by Springfield Custom at 2 lbs 14 oz...sounds perfect. I run my game 1911's at 3 lbs. But travel, break, reset all matter also and it sounds like some of the companies above have manufactured their own parts. Would appreciate some feedback from those who have game triggers on their XD's and XDM's and who did them. If there is another gunsmith I've missed by all means let me know. This will be strictly a game gun. Thanks!

Thanks, Chet Talk about being responsive to customer needs! Dawson is awesome (does that rhyme? ).

Hey Chet, How about a White Dot or Tritium Dot front sight for the XDM 5.25? I tried a Dawson fiber optic front on my 1911 but just didn't like it (used it for a year). But I like more than a plain black blade. A white dot is just right for my eyes to pick up quickly against a plain black rear. Here's my vote for a white dot front sight for my XDM 5.25 (I don't really need the tritium, but that's how you make them and will do just fine!). Thanks.

Thanks for the feedback everybody I got a PM with a tip on some Wolf LPP's so I'm ready to go as soon I they get here! Bill

Hello Everyone, I'm new to Brian's forum, and just spoke with him in helping me to get started reloading 45 ACP. Will be going with a Dillon 550, but here is the hardest part - Large Pistol Primers. Thought I would start this topic so folks could post links to any place they have found them recently (like in the last 10 minutes!). I know they will go fast, so the links you add might only be valid for a few minutes, but post away if you know of any place. Here is my story from yesterday. Knowing I was going to start reloading, I added my email to the "Notify Me" on all Large Pistol Primers at Midway about a month ago. Came home last night and had a notification from Midway that Winchester LPP's were in stock. The email had arrived at 4:18pm. Clicked on the link immediately, and they were already out of stock (5:32pm). Called Midway today, and they said they sold all 300 boxes of 1000 in about 20 minutes. I live in Murfreesboro, TN and the guns shops around here (and Nashville) haven't seen any LPP's in about 9 months from what they tell me. Thanks for any info anyone has. Bill