Glock KB's

[Dan]

This forum seems to have a wide variety of shooters with differing backgrounds and experience levels, but everyone who posts has valid and intelligent opinions.

Now, I would like to hear from Glock shooters who have actually had a KB, and what the cause of it was.

I have posted this because of all the hearsay Glock KB stories shooters seem to have. You know, my uncles best freinds son's Glock just blew up when he pulled the trigger....

If it happened to YOU lets hear about it.

Thanks,
Dan

[motorep]

MarkCo,who is on this list, had a barrel replaced by Glock. I'm not sure if it KaBoomed, but it was bulged. I'll email him and see if he'll enlighten us.

[MarkCO]

This post might make some people mad, but that is okay. Here goes. First, I work as a forensics engineer (mechanical) and, professionally, I investigate failed products as an expert witness. I have conducted extensive testing on the issue of KBs in Glocks and especially the Lead issue. I have examined 14 blown Glocks to date (including one of my own). I have tested thousands of rounds in Glock barrels, aftermarket barrels and polygonally rifled pressure barrels. There are several factors at issue with Glock KBs. When related to the .40 it is a high pressure round and hot-rodding it will cause damage and injury. Heavier bullets are more likely to increase pressure due to reloading practices and quitre possibly handling of loaded ammo. Also the polygonally rifled (Glock) barrels do lead excessively causing increased pressure. I have conducted pressure testing with instrumentation and the pressure ramps up with each successive round of lead down the barrel. Lowering your velocity can actually increase the leading rate with some bullets. The laser Cast is not the answer either. It too leads, it has more gas cutting and may appear to not lead quite as much but you are still decreasing the cross-sectional area of the bore by "soldering up the bore". Now the solutions. Either use plated bullets ($12 more per 1K) or buy an aftermarket conventionally rifled barrel ($70-$200). Also, my test data has been confirmed by Glock reps and armorers and accepted into court as fact! Points to take with you. The 40 is a high pressure round to start with. Glocks and Lead lead to higher pressures. Heavy lead bullets at pretty high velocities accounted for KBs in 11 of the 14 Glocks I have examined. I personally have aftermarket barrels for lead but use Berry's plated bullets in Glock barrels almost exclusively. I avoid the heavier bullets in my reloads and in factory ammo (definately no 200 grainers in the 40 for me in a Glock). I shoot Cor-bons 150 grain in my G27 for a carry round. Feel free to e-mail me if you want more info. Now for the other 3 blown Glocks. One was a G30 shooting a jacketed bullet. Got a double charge of Bullseye that was near max anyway. Case rupture split the frame, blew the mag out and sheared off one of the four guide rails. Barrel was undamaged and is still in use today. Shooter had a slight abrasion on his strong hand thumb and a blood blister on the palm (from the cracked frame) and a wet pair of shorts. Another one was a G19 that had approximately 1500 rounds of commercial lead fired through it. Near chamber bore dimension due to leading was 0.323 inches after the KB. Cracked the frame, split the chamber horizontally for a depth of about 0.5 inches. Slide assembly lifted up and jammed bending 3 of the four slide rails but no breakage of the frame. Glock owns that one now. The other was a G22 (this one was mine, about 8 years ago) shooting 155 grain lead (about 16.5 BHN that was supposed to be 22 BHN) at moderate speeds. About 700 rounds fired since last cleaned. Failure similar to other lead and Glock failures except with a 155 grain slug. Slightly cracked chamber, one cracked rail and one bent rail. Glock determined excessive leading as cause of failure. Glock replaced the gun. Interesting thing to note here, 14 blown Glocks and the worst injury besides soiled shorts and bruised confidences, a blood blister and a sprained finger here and there. Not one slide separation and not one grenaded chamber. Can not say that for other blown guns I have examined. A blown Beretta or a blown 1911 is sure to severly injured. Glocks are very strong indeed. I have seen a couple of other blown Glocks but did not have the chance to examine them. One of these was reportedly a .40 (G23 belonging to a Cop) shooting Fiocchi FMJ departmental practice ammo. Somehow the remaining loaded rounds in the mag had the bullets seated 0.11 inches deeper than the rounds left in the box. It was the 3rd round in the mag that blew and the cases from the prevoius 2 were buldged extremely. The case is in litigation. Good Shooting, MarkCO

[4V50 Gary]

Hat's off to you MarkCo for an excellant peice.

Gary

[Rob Pincus]

Mark, thanks soooo much for that post. Now if we can ever get the masses over at rec.guns to come read it they'll stop flaming everytime I advise them not to use lead in their Glocks. OTOH, to hell with 'em.

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-Essayons

[MarkCO]

Thanks for the accolades guys. I try but there are a few Glocksters out there who wish to stay in the rain. I just hope I don't end up on the other side of them in court. To Glock's credit, the design is strong. And really, what is $100 for another barrel anyway? Good Shooting, MarkCO

[MarkCO]

I wanted to raise one more issue here about Glock KBs. The aftermarket dual recoil assemblies can also induce KBs. Yes, it is true that the Baby Glocks have a dual spring set-up from the factory but they are not the same design nor do they work in the same manner. I have tested a few of these (I have never fired a Glock with one of these) mechanically including dry firing and firing over primered cases. Some of these systems will actually bring the slide out of batterey when the tirgger is pulled. Some are worse than others, but, I have seen several of these cause damage to guns and shooters. Some also affect the pressure curves. This may actually be more dangerous than the lead issue since the strength of the gun is not available to contain the energy. I omitted this in my first post because I wanted to check a few things and I can not give specifics of the cases I have seen. Even stronger than my warning against using lead in Glocks, DO NOT use these aftermarket recoil reduction systems! Good Shooting, MarkCO

[Steve Koski]

MarkCO,

I would like to see your data from the pressure testing with lead in Glock barrels. Please post it here or email it to me at [email protected]. Your sentence: "I have conducted pressure testing with instrumentation and the pressure ramps up with each successive round of lead down the barrel." makes me wonder if you're being completely straight forward with us. If you've done much pressure testing you know that the pressures vary significantly from one round to the next. Some cartridges exhibit extreme spreads of more than 5,000 psi. With the inherent variation in pressure testing I find it hard to believe that somehow each reading was higher than the last. If you'll put up the data I'd be glad to eat crow on this, I'd just like to see the data.

My kB!

The very first day I reloaded I was using 155 LRN and Universal powder. I loaded 5 rounds up at 5.5 grains measuring each charge on my powder scale. I didn't own a powder measure at the time. I then loaded 5 rounds at 5.6 grains, and 5 at 5.7 grains. When I went to move the scale to 5.8 grains I accidentally moved the grains to 8 instead of moving the 1/10 grains to 8. The next 5 rounds I loaded up were at 8.7 grains. The manual listed 6.0 as maximum. Needless to say when I pulled the trigger things weren't fun. The magazine ejected, magazine catch broke, magazine broke, the slide stop lever broke, and several other parts in the frame were damaged. The chamber had cracks down each side. They didn't open up, but if I hold it in the light I can see definite cracks. I had a small blood blister on my right hand where the other side of the magazine release struck my hand.

I sent the gun back to Glock who replaced the barrel and a hand full of internal parts for $170. Clearly "lead" was not a factor, neither was "Glock." It was 100% due to reloader error, my error.

I have since reloaded and fired over 14,000 rounds of lead bullets through my Glock 40's with out any incidents whatsoever. I follow several rules:

1. I shoot good quality cast bullets.

2. After 100 to 150 rounds of lead I shoot 3 or 4 jacketed rounds to clean the lead out. I won't do this if leading is anything above "really minor," which it never has been.

3. I clean the gun after each range session and make sure there is very little or no lead in the bore. If there is a bit left the next time at the range I'll fire a few more jacketed rounds. This cleans it up perfectly. If there is any significant lead at all I'll clean it out 100% before returning to the range, but like before, this has never happened.

4. I load in the low to middle end of the range. I don't push the velocity envelope with lead bullets.

5. I load all of my 40 rounds at maximum COL. I don't see any reason not to. They feed great and I believe this helps keep pressures down.

6. I load mostly 155 grain bullets. I have loaded some 180's, but I prefer the 155's as they recoil a bit less, and I believe they develop less pressure than the 180's.

7. I discard cases only when they split. This almost always over 15 firings, and occasionally as high as 24.

With good practices lead bullets can be safely shot through Glocks. If you don't care to follow rules, clean your gun, check for lead buildup, or reload responsibly then you should definitely not be swayed by the low cost of lead bullets. You should buy commercial ammunition.

But I guess Rob knows best...To hell with me.

[This message has been edited by Steve Koski (edited 11-16-98).]

[MarkCO]

Steve, there are several issues related to guns that I know a little about, this issue, I know a lot about. Not only have I worked on it professionally, but it is a hobby too. I used several methods to measure pressure including Oscilloscopes and FFT, transducers, strain guages, piezo electroincs, etc. I never saw peak pressures deviate by more than 2000 psi round to round and with jacketed, no more than 1200 psi round to round. 5,000 psi variations imply large velocity variations on the order of more than 100 fps. That is way too much. When I quote numbers, I have used conventional statictal methods or standard mathematical analysis to determine them. I started out with a 33,000 psi round with a std dev of 719 psi. After 500 rounds with jacketed bullets, the pressure was 33,000 with a std dev of 823 psi. After 50 rounds with lead, 34,200 psi, 100 rounds 35,100 psi, 150 rounds 38,800 psi, and at 200 rounds 41,000 psi, 300 rounds 45,000 psi. The last few started to have greater std devs approaching 2000 psi, but the results are still statistically accurate. Notice this is NOT linear. Also the velocity started to climb at about 5 rounds fired, by 50 rounds it was 40 fps higher than the first round. By 100 rounds it had climbed by about 90 fps. At 150 rounds, 80 fps higher and at 200 rounds it was about 30 fps higher. Velocitites are all averages with no std dev exceeding 30 fps. Also, realize that this was in controlled conditions with each charge hand weighed, and tight chambers in pressure barrels. Hope this satisfied your curiosity. Good Shooting, MarkCO

[Rob Pincus]

Steve, did you say that you rfire jacketed rounds to "clean out" your barrel??

Obviously, you've survived this long and whatever works.. works. BUT, I have been told by several people I trust (some of whom are in Smyrna) that many of these Kb!s are cuased by just that practice. IOW, letting lead build up and THEN firing the jacketed rounds. The theory being that the jacketed rounds "give" less than the lead and react more dramaticaly to the leaded up barrel.

be careful.

-Rob

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-Essayons

[wolfz]

MarkCO,

Can you be more specific on your warnings of the after market recoil systems? Are you talking about Spinco, or Harrt's?

[Rich Lucibella]

MarkCO-
I love first hand research. Yours is especially valuable in this most controversial (and myth plagued) area.

Thanks for sharing it with us. Good stuff.
Rich

[MarkCO]

Steve, Dan is right on with the jacketed after lead issue too. Did not want to harp on you too much in one post, but it can actually increase the likeliehood of a KB. WOLFZ, As for the recoil reduction systems. ALL aftermarket DUAL ACTION or DUAL RATE recoil spring systems have this problem. Stick with a stock configuration. Unless it is the G26, G27, or G33, factory recoil assemblies, and suitable aftermarket replacements, only have ONE spring. The Mini's have a dual spring from the factory, but it is not dual rate. Sorry, but if you bought one, you got a bad deal. Try to return it is all I can say. Good Shooting, MarkCO

[Steve Koski]

MarkCO,

Thanks for the clarification. Thank you very much for posting the summary. The "each successive round" statement was what threw me off. Certainly it is feasible that round 47 was 34218 psi and round 48 was 34183. If you had said "there is a clear and increasing trend" I wouldn't have tried to call your bluff. You have earned a greater measure of my respect.

What make/hardness/weight/shape of bullet was used in the testing?

Rob, MarkCO,

Read point #2 above. If the leading is anything above minor I don't do the "shoot the lead out" trick. This has never happened. Also, my jacketed rounds are loaded in the low to mid range, so I doubt an increase of 2,000 psi is going to exceed 35,000.

More things to consider:

If I had cases failing at 4 or 5 loadings I'd be worried that I was reaching some high pressures. My cases almost never split before 15 firings and 18 to 20 is more typical. Additionally, the case bulge at the feed ramp is almost nonexistent on my reloads. If you hold a fired reload next to a fired factory round the bulges are worlds apart. On the reloaded case it is dificult to tell which side of the case was down (in the unsupported feed ramp area.)

What kind of case life are you guys getting that load 'em hot? Any IPSC shooters goin for major?

Both of you need to remember that reloading is a gamble, no matter what components you use. The more you know and understand about the process, the more you can control the risks. I've learned a way to control my risks that has resulted in a perfect safety record (since my overcharge kB!). If you don't understand how to lead climb rock faces then don't do it. If you understand how to do it safely and responsibly, and it suits your fancy, then more power to you.

Compound Recoil Springs:

I bought one at a gun show from "On Target". It worked great for about 200 rounds then the gun started shooting high. I noticed that the gun wasn't going completely into battery. This out of battery condition kept the barrel pointed slightly upwards and resulted in the rounds striking the target 2 to 4 inches high at 10 yards. When the gun was clean it didn't do it but I suspect that a little powder residue on the locking surfaces was enough to keep it a bit out of battery. The other phenomenon that could have been at work was "spring set." All springs will have a shorter free length after having been cycled a few times. I see this all the time in my Wolff recoil springs. No further shortening of the springs occurs once it is "set." Perhaps after a spring takes its "set" it exerts less force at the extended position.

Knowing this I took a bathroom scale (I know it's crude, but it's all I've got) and tested a factory new recoil spring for a G23 and the "On Target" spring. I had to put 7 lbs of force on the factory spring to just begin to compress it. I only had to apply 3 to 4 lbs of pressure on the "On Target" spring to begin to compress it. I know these readings aren't real accurate, but they do give a good basis for comparison.

Conclusion: The outer spring (the only spring acting at the near extended position) on the aftermarket unit didn't provide enough force at the nearly extended position to push a mildly dirty gun into battery. The factory spring still had plenty of umph and always put the gun into battery no matter how dirty it was.

I believe that if the outer spring was replaced with a factory strength spring then it would be every bit as safe as a factory spring, but with the added benefit of the internal spring to provide additional resistance just before the slide reaches the full rearward position. This would further reduce the slide velocity when it contacts the frame and would probably extend the life of the gun, not to mention reduce the recoil impulse.

If the above was true why would a compound spring be unsafe? By what mechanism?

I'd like to know by what mechanism a compound recoil spring assembly could cause a gun to go out of battery as the trigger is pulled. Please explain more on this subject if you would please MarkCO. The only mechanism I've been able to think of to explain this is that if the outer recoil spring was REALLY weak then perhaps the resisting force of the trigger bar disengaging safeties and/or compressing striker springs could over power the recoil spring. This would result in the slide being pulled rearward when the trigger is pulled.

Anyone care to share another mechanism that would possibly explain this?

MarkCO and Rob,

Don't take anything personally. I really apppreciate your input. It's been educational.

Sincerely,

Steve Koski
[email protected]

P.S. Can you tell I'm an engineer?

[This message has been edited by Steve Koski (edited 11-17-98).]

[Dan C]

This has been a great discussion, so says another from the pocket protector set. Well put, Steve and MarkCO.

[MarkCO]

Steve, I'll try to answer your questions in turn, if I can remember them all.

First, bullets. All in .40 S&W BTW. I ran tests with Hornady, Professional Shooters Products, Colorado Cast, Bull-x, Oregon Trail, Impact, Legend, A-zone, E & E, National and a few hand-mades. Weights were from 135 grain up to 200 grain. I ran all of my tests with the Impact 180 grain SWC to establish a baseline. I ran the others more sporadically to compare against my baseline. I also ran more extensive tests on the A-zone (the softest decent bullet with BHN of 16.5) and the Oregon Trail (the hardest with BHN of 23.9) to make sure I bookended my results so to speak. I tried to stick with a FP or light SWC profile, but not all were available. I also compared the bevel-base designs against the flat-based designs. I also did extensive testing of the bullets for composition, concentricity, weight, hardness, and other physical properties.

Second, I have seen moderate spikes with the jacketed after lead practice, however, my pressure barrel was much stiffer and that could have some effect on the spikes. The "pushing the dam" effect is really what scares me and I never tried after more than 25 lead rounds.

Third, In my "standard rounds" (pf of about 165) I get a bulge of about 0.0001". By contrast, the Cor-bons buldge is like 0.0015" Accordingly, I do not reload the fired Cor-bon cases. I have some .40 brass with more than 15 firings on it. One case mouth split so far, total. In my IPSC loads (pf of 185), bulge is about 0.0004" and I fire them 3-4 times and downgrade them to my steel loads which do not expand them at all (pf of 135).

Third, yes reloading is dangerous. But so is driving a car. Do things to protect yourself like always visually checking powder level before seating the bullet, double checking charges, etc.

Fourth, Recoil Reduction systems. You had exactly the situation that is unsafe, although due to chamber debris. The light initial spring can let the trigger pull pull the slide out of battery. Take you recoil spring out, and pull the trigger. The slide will move around and back. Alot of guys were using these with 3.5 pound connectors with no problems, switch to a 5.5 or 8 pounder and you will pull the gun out of battery. I have seen this on more than one gun. Your conclusion that making the first spring stronger might serve to make these systems safer. My preference would be at least twice the trigger weight. That gets you real close to stock weight anyway. If you want lighter recoil, use lighter loads. My steel load is a real pussycat. My thought is that if you put a stronger spring up front, you would conversely need a weaker second stage spring to compensate. We only have so much energy to use (F=kx). I much prefer to tailor my spring rate to the gun. Aftermarket spring kits without a captive rod and a 3 spring pak are like $25 from Wolff Spings. This is a much safer and, to the engineer side, enjoyable venture. I have recoil spring weights from 12 pounds all the way up to 21 pounds for my G22.

Steve, I think I covered the points, LMK if you want more clarification. From the e-mail messages I have been receiving and the messages on other boards, this has been a very enlightening discussion for many. If nothing else, I thank you for being a "sparring partner" so to speak and for asking for clarification. I tend to have these gaps where I do not know how to fill them in. I either get accused of technobabble or not providing enough information. Good Shooting, MarkCO

[Steve Koski]

MarkCO,

I have since retired the On Target recoil reduction system. Several times I have written them asking them to back up their lifetime warranty. They never return calls or letters. I even ran into them at a gun show. They said they'd send me a corrected unit, but they never did. If you are considering buying one of these, don't.

For carry I use a factory Glock spring. For G23 practice I purchased a non-caputure SS guide rod from Glock Works and a handfull of Wolff recoil springs. I generally use a 24 lb recoil spring. One might think that I would have some reliability problems using such a heavy spring (factory is 18), but I haven't had any. Even light loads (4.5 gr WSL 155 LRN 1,135 COL) function perfectly. It's my experience that the heavy spring seems to reduce the felt recoil a bit.

9mm vs 40 springs:

I believe that the Glock 40's are undersprung. They should have stiffer springs than their weaker sister 9mm pistols.

Assumptions
1. most 40 bullets have more momentum (higher power factor) than do most 9mm loads.

2. The 9mm barrel and slide weigh the same as the sister model 40 barrel and slide.

3. At the instant the round leaves the barrel the frame is stationary.

4. Momentum is conserved (pretty safe assumption eh?)

This means that the 40 slide/barrel have a greater momentum, and hence velocity than a 9mm slide/barrel. So why does the 40 have the same spring as the 9mm pistols?

I have two theories:
1. Glock doesn't want someone to get killed in the line of duty because he accidentaly put a 40 spring in a 9mm pistol and it didn't cycle.

2. The increased wear doesn't override Glock's concern about item #1.

What are your theories?

Take Care,
Steve Koski

[BillOH]

Does any one have any info on KB's in Glock 17's? I have only shot jacketed bullets in mine until recently when I started shooting 147 RNL to get a light recoiling load for IDPA. Bill

[Mikie]

I have never had to purchase after market add-ons to any guns I've owned. That's why I'm surprised at all of the Glock add-ons available. In my opinion if the gun as delivered from the factory doesn't function reliably unless you, change the springs or guide rod or something else, it's not worth owning to begin with. Furthermore I couldn't endorse a company that doesn't put the right components in the gun they're selling you right from the start. I find it hard to believe that Glock would put the same recoil spring in a 40 as a 9mm. This should be a question that we don't need to speculate on since Glock can answer directly. This concerns me greatly as I am a new owner of a Glock 23. Please someone tell me that there is a heavier spring in a 23 than a 19 or explain why the laws of physics don't apply.

[Steve Koski]

Mikie,

Before you get too excited remember that people get extremely good life out of their 40 Glocks. Yes, the springs are the same between sister 9mm and 40 Glocks. I highly doubt that Glock is the only company to do this. Someone should call Glock and ask them this question and post the response. Maybe I'll do it...

...Jean in the Glock warranty department said "Because Mister Glock doesn't feel that it needs a heavier spring." I guess if we want further clarification we need to talk to Gaston himself. He's probably right, as service life is very good, much better than most (if not all) of the competition.

Take care,

Steve Koski
[email protected]

[This message has been edited by Steve Koski (edited 11-19-98).]

[WStringer]

I will try to cut right to the matter at hand. I was attending a Jim Crews class in Oct of this year and had my Glock 21 blow up in my hand. This load I was shooting is the same load I've been shooting in my 1911 for the past six years. Needless to say I've never had a problem with it, up to now.

The load was a 200gr plated bullet with 7.7 gr WAP. I was using a Winchester primer.

To myself and others in the class, it seamed that the handgun fired out of battery. The failed place on the shell was on the bevel just before the head stamp. The reason this seams odd to me is that the round I was firing was a low persure round. When I took the gun to Glock I got a cold reception and a we will fix your mistake for x amount. I paid to have my HG fixed.

I would like to know if any one has had this type of problem and what happened. Did Glock try to help them or what.

Thanks for your help.

[MarkCO]

To all who e-mailed me last week, I promise to respond by Wednesday. I got a ton of e-mail and I was out of town a few days. I'll also try to respond to some of the other questions on this thread later. Good Shooting, MarkCO

[MarkCO]

As for recoil assemblies in the .40, I agree with Steve on this. I use a 22 pound spring with my IPSC load. 52,000 rounds on my G22 and still kicking. The wear with a standard factory srping will be a little higher. I can go all the way down to 130 pf loads without any misfeeds with an old stock spring. A 110 pf load requires the use of a 14 pound spring. Next, Glock is probably a little light in their stock spring in all .40s. Especially if you shoot major IPSC loads or Cor-bons or some other high energy round, you should most likely step up to a stouter spring. Also, remember that springs DO NOT have infinite life. Had an acqaintance that said his Glock sucked and sold it at the gun show for $300. He bought it used with about 30,000 rounds on it and put another 20,000 rounds through it before it started to have trouble. Boy did his face drop when I told him it was probably the recoil assembly getting weak. Went back to the gun show and the buyer said he would sell it back to him for $350. He did it and put a $10 part in it and it has worked ever since. As for the aftermarket parts, Glocks are great right out of the box for the vast majority of shooters. However it is folks like us who compete, tinker, etc. that want to try other things that has fueled the Glock aftermarket industry. For my G22, I easily have $350 in mag extensions, triggers, recoil assemblies, and other parts that I use. They increase my speed and the handling capabilities of the gun. Not necessary for combat or carry (my carry G27 has absolutely no mods at all) but good for competition. GStinger, your load is actually over max for that powder with a Ranier bullet. Berry's maybe right at max. Plated bullet load data is a tad sketchy. The load would be over max for lead and this is where the load data for plateds should be derived, NOT from Jacketed. In my opinion, you were over max! Even so, unless you had severe stripping of the jacket in the bore (not likely with the 45 velocities) the Glock could have handled the overpressure. I would suggest you recheck your loading practices for other possibilities too. I have seen Glock bend over backwards in customer service even for shooter error. I do not think that they have any real responsibility in your case based on the limited information you provided. Good Shooting, MarkCO

[Mikie]

Steve and MarkCO,

Thanks for the encouragement and information. Sorry if I sounded overly concerned but the same recoil springs in the 40 Glocks as the 9mm Glocks doesn't make sense because of the KE issue you raised. Not that the 40 won't work with the same spring but the obvious result is more felt recoil. This actually makes sense based on my observations. I have put 425 rounds through my G23 and have not had one malfunction. The gun prints about 3 inches high at 25 yds which doesn't really bother me. The recoil is manageable but compared to my USP40C the G23 is more noticeable. I know comparing the insides that the USP has a nylon buffer around the guide rod but the lower bore axis of the G23 I thought would reduce the muzzle rise. Overall I like the G23 anyway and I was fully intending to leave it alone. Now I might consider getting a higher tension spring, especially if the recoil is reduced. If I go this route does the bullet weight I fire matter with regard to what tension spring I should get?

[MarkCO]

Mikie, just like a highly cutomized 1911 with different loads, you can do the same with a Glock. It is not an exact science and requires some time at the range and loading bench, but it is well worth it. You can tailor loads to certain shooting disciplines. For instance, IPSC major is 175 pf, thus you can make a load/recoil spring combo that works best in your gun and to your perception of recoil etc. by adjusting spring reates with different loads. Likewise, an IDPA load might be like a pf of 160 and a steel load a pf of 135. I have a light target load that I use for techniques practice with a pf of 110 out of my G22. It requires a light spring as it will not function with a regular stock spring. Good Shooiotng, MarkCO