Anyone who has a 1911 .45 ACP might well feel he has the ultimate self-defense handgun, and there is much evidence he may be right. But some will not be satisfied with that power level, never mind that it does the job most of the time.
For those shooters, more power is readily available. For instance, there are drop-in barrels that can turn your 1911 .45 into a hot .40 (.400 Cor-Bon), or a hotter .45 (.460 Rowland). How good are these? We didn’t know, so we acquired some drop-in barrels from Storm Lake in .400 Cor-Bon ($130) and from Clark Custom Guns in .460 Rowland ($275).
Also, there is at least one complete gun that offers a purported step up in ballistics, the Guncrafter Industries .50 GI ($2895) Model No. 1 pistol, which is a 1911 dedicated to a .50-caliber cartridge with a rebated rim. The ammunition for all three test calibers was proprietary but easily obtained, as we discovered. Here are our findings.
Alex Zimmerman took the custom 1911 world a giant step farther when he came up with the idea of a .50-caliber cartridge that would fit into the “footprint” of a 1911. While the .45 ACP has a good fight-stopping record, it’s not perfect. Nothing is, but more gun is almost always better. We heard about the .50 GI two years ago from a friend of Gun Tests. We liked the idea, especially considering that the .50-GI’s cartridges would not make the 1911 grip any bigger. Was it possible to get more “gun” into a 1911? Yes. Does the .50 GI indeed offer more? You bet it does!
The gun is not inexpensive. Zimmerman, head of Guncrafter Industries in Huntsville, Arkansas, decided to make his 1911s as carefully and as well as any have been made to date. After we examined our test gun, we felt that he had indeed done so, and felt the asking price (same for .50 GI or .45 ACP) was well justified, and in line with the best custom 1911s by other makers. The gun was extremely well made, and that’s only the first thing we noticed. We got some of the two available types of ammo from G.I. to try in the test gun. Ammo is $14.25 for 20 rounds of 300-grain JFP, or $15.75 for 20 of a hotter 275-grain JHP. While low-cost surplus ammo doesn’t exist, Guncrafter helps the shooter by offering reloading dies, brass, bullets, and reloading data from the company website (www.guncrafterindustries.com). Bullet diameter is 0.500 inch, same as used by the .50AE and .500 S&W Magnum. For the record, Linebaugh’s .50s use 0.510-inch bullets.
This pistol was one of the tightest-constructed 1911s we’ve inspected. The frame and slide were machined from forgings. The overall look was pure business, with olive-drab checkered aluminum grip panels contrasting nicely with the Parkerized steel. Lockup was with a slight click, more felt than heard, as the parts went together with zero rattles and zero slop. Unlike another makers’ guns that lock so tightly they need hundreds of rounds to break in, the .50 GI was pleasant right from the start. It took good strength to open the gun, and we found it easier to cock the hammer first, but it didn’t take a Schwarzenegger to get it open. We applauded the lack of a barrel bushing, and the fine fit evident at the rear of the slide. We noted the complete lack of loose parts, and that the metalwork, finishing and fitting everywhere were absolutely first class. We wondered at the Parkerizing finish, but it works very well. For $200 you can get a hard-chrome finish. The finish was well done, and perfect for a fighting handgun. The fixed sights had tritium inserts. There were no sharp edges anywhere to cut the hands of shooters practicing clearing drills, or to gouge your holster. Clearly, the maker understands fighting handguns.
The trigger was excellent, no surprise once we realized what a fine piece of work we had in our hands. The Videki-pattern trigger broke cleanly at 4.8 pounds, was well fitted in its slot, and was perfectly adjusted for overtravel. We had expected a heavy gun, but were happily disappointed. Yes, it was a touch heavier than a .45 ACP, 41.6 ounces empty versus 38 ounces. The handling, however, was identical. The grip circumference and all external dimensions were identical between the .50 GI and several 1911s on hand. It fit our favorite Bachman Slide holster perfectly, and we could not notice a difference in the holster between this .50 and a .45. The easily loaded magazine held seven rounds. The magazines were slightly thicker than .45 magazines. There is an optional .45 conversion for $365 which must be fitted, and fitting costs $115 if done by GI. If you already own a Guncrafter .45 ACP Model No. 1, it costs the same to convert it to .50 GI. After our experiences with the big .50, we doubt anyone would want to mess with a .45 — except to make use of low-cost ammo.
As we prepared to press the trigger of the .50 GI on a live round for the first time, we didn’t realize we were in for one of our finest surprises in many years of testing guns. We expected a nasty kick. It never happened. Instead, after a few rounds, we tried a series of double taps with the .50. To our joy, we could easily control it as easily as a .45. Our rounds landed exactly where we would have expected them to land with the .45 ACP. We were hooked! This gun had it all, we thought. It had significantly more power than the .45 ACP in an easily controlled package that was essentially the same size and weight as the one we thought was the ultimate self-defense handgun for many long years.
There are two “normal” loads for the .50 GI, one with a 300-grain jacketed flat-point bullet at a nominal 700 fps (actually 712), and a 275-grain JHP at a nominal 875 (actually 890). [PDFCAP(2)] told us Guncrafter was honest in its velocity claims. The 275-grain load gave a touch more felt recoil, and did seem to have some muzzle flash, but in no way did we think either was objectionable. Accuracy was generally five shots touching at 15 yards, from both types of ammo. Our test shooters regularly got such groups, and did so with ease. We did notice a touch more recoil with the .50 GI than from ordinary .45 fodder, though some hot .45 rounds kick as much as the .50 GI. This .50 definitely had authority that was unmistakable on target. Compared with the .400 Cor-Bon and the .460 Rowland, the .50 GI was far more shooter friendly. The .400 and .460 had more blast and recoil and operated at higher pressure, and battered the gun and shooter more. Although the .460 Rowland gave hotter results on paper, we’re not entirely comfortable with all that blast and kick from the 1911. The .50 was much more pleasant.
This was a beautifully machined barrel, marked over the chamber “STORM LAKE 400.” When we spoke with Storm Lake, we also asked for, and received, a barrel chambered in .45 ACP, for a different test at a later date, so we had two SL barrels on hand. The management of Storm Lake was taken over about two years ago by Machine Solutions, and they made some radical and much-needed changes to barrel production. Several years ago we obtained a Storm Lake drop-in 1911 barrel in .45 ACP from a catalog supplier, but that barrel didn’t even come close to dropping into our test gun. One of the critical dimensions was way off. We wanted to see if the new management had corrected that flaw.
Neither Storm Lake barrel had the link and pin. If you order one of these “pre-fit” barrels from, say, Brownells, the kit ($169) will come with a link, pin and bushing. But you can also order just the barrel directly from Machine Solutions for the price given above (www.stormlakemachine.com). The company normally stocks barrels in .45 ACP ($125 for the barrel alone), .40 S&W, 9mm, .38 Super, .357 SIG, and a few in 10mm. (They also make barrels for several Glock models.) They can cut a .400 Cor-Bon chamber into a .40-cal barrel on request, which is what they did for us.
Our test gun was a Don Fisher-modified Norinco 1911. It is a fully functional, adjustable-sighted, well-made copy of Colt’s 1911 A1. We stripped the gun and attempted to insert the Storm Lake .400 CB barrel. It didn’t fit. There were two slight bumps, one on each side of the link base. The other Storm Lake barrel didn’t have those bumps, so we removed them with a file, hand grinder, and polishing buff. Then the barrel would enter the slide fully, and that’s when our real troubles began.
On carefully measuring this barrel and half a dozen others, we found we would have to remove 0.030″ from the rear of the chamber mouth before we could get it to fit. A phone call to Storm Lake (Machine Solutions) gave us the answer. Bad luck had given us one of the barrels made by the previous company’s management. We had needed the .400 Cor-Bon barrel fast, and that’s how we got it. We didn’t give them time to check it, so we feel the problem was related to our editorial need, not to the new and very knowledgeable ownership of Storm Lake. All our questions were answered to our satisfaction, and we were assured this will be the last barrel to leave the company with incorrect dimensions. (There may be some floating around out there, and if you mill away the extra metal they can be made to work.) We tried the newly made .45 ACP barrel, and it fit our test gun perfectly. It had excellent workmanship. We have no qualms whatsoever about Storm Lake’s barrels.
We were out of time, or would have sent the barrel for correction. Instead, we ground away the rear of the barrel (not the shroud) almost as far as was needed, and then fitted it to the gun by hand. Then we headed for the range. Our test ammo came from Cor-Bon, the company that invented this caliber. We tested with 165-grain JHP, 135-grain JHP, 135-grain PowRball, and with Blue and Silver Glaser Safety Slugs.
Our first experience with the 165-grain JHP Cor-Bon ammo told most of the story. We experienced more recoil than with most .45 ACP loads. With each shot the gun gave a loud bark and kicked sharply toward the sky. We had occasional failures to feed with all the ammo, but we attributed that to our hurried fitting, which gave a discontinuous ramp. Careful fitting would improve feeding. The 165-grain loads fed and ejected well with only one failure to feed. The Blue Glaser Safety Slugs produced a huge fireball, and when we tried ‘em on paper we got a 10-inch pattern at 15 yards. We declared them to be useless in this setup. The Silver Glasers shot well enough to be useful. We didn’t much like the 135-grain JHP loads because we could feel them battering the slide. They gave the poorest feeding of all. The slide seemed to bounce forward so fast the next round could not rise in the magazine before the slide jammed it against the ramp. A stiffer slide spring might help, as might a better feed ramp, but the rounds actually struck the ramp within the frame and lodged there before they got to the barrel ramp. Be aware your gun might need twiddling if you want it to work perfectly with .400 Cor-Bon, and then it might not work with .45 ACP. Our test gun would remain a .45, so we left the ramp alone. If we set up a 1911 as a full-time .400 Cor-Bon, we’d install a buffer and a stronger slide spring. The Fisher Norinco did have a heavy, progressive .45-type spring, but it may not have been enough.
The brainchild of Johnny Rowland, TV outdoors personality (“The Shooting Show,” cable TV), the .460 Rowland was intended to make the absolute most of the .45-auto concept while staying within the basic 1911 size. (You can get a revolver rechambered to .460, too.) To do this, Rowland went to a special strong cartridge case enough longer than a .45 ACP case that it will not chamber in a standard .45 Auto. The .460 Rowland ammunition pushes the .45-caliber 1911 envelope close to its limits. As any .45-auto shooter can tell you, recoil with some plus-P .45 loads is getting right up there. To boost the velocity of a 230-grain bullet to over 1000 is pushing things. But to boost that same bullet to nearly 1400 fps…Zowie! Clearly a muzzle brake looked like a good idea.
The .460 Rowland kit included more than just the stainless-steel barrel, hence the extra money. There was also a bushing, link, heavier slide and firing-pin springs, a two-piece guide rod for the 24-pound spring, and hanging out front, a big muzzle brake (your choice of blued or stainless). All the parts were well made and, as we found, well thought out. We told Clark we would put this unit into a Norinco. The Clark website (www.clarkcustomguns.com) noted that Norincos like our test gun may require some minor fitting, but ours didn’t. (Be sure to check the Clark website’s FAQs before you place an order. Some guns are unsuitable for this conversion, and Clark makes that very plain. If you have any questions or doubts about your 1911, ask them.) The whole apparatus went easily into our gun, with exactly no fitting required. That’s how we define “drop-in.” Clark Custom Guns clearly speaks the same language we do, and their workmanship here was outstanding. Clark recommends sending in your slide if you doubt your ability to make the kit fit. One nice touch was that the last few threads of the two-piece spring buffer required the use of an Allen wrench (included), with the idea of keeping all the parts of the gun together under severe and continued recoil. We thought this was a good idea.
The installation required more than two hands. We found it easier to hold the slide in a padded vise while we installed the kit. The instructions made everything clear, but didn’t suggest a vise. We had mixed feelings about the muzzle brake before we fired the gun. It was 1.5 inches long, adding that much to the overall length of the 1911 along with noticeably more weight. It made the gun too long to fit most holsters, but our Bachman Slide didn’t care. We found the extra length made presenting the gun harder and slower.
Clark offers both Starline brass ($25/100, and normal .45 ACP dies work fine) and ammo, the latter made by Georgia Arms (770-459-5117, or 1-800-624-6861, www.georgia-arms.com). We got three types of ammo in two bullet weights. Prices varied from $24 to $32 per fifty rounds. We noticed discrepancies between the ammo designations and claimed velocities between the Clark website and the ammo provided to us by Georgia Arms. Because Georgia Arms made our test ammo, here are that company’s catalog numbers and claims, with our measured velocity in parentheses: G460A = 185-grain Nosler at 1550 (actual 1440); G460B = 185-gr. JHP at 1400 (actual 1375); G460C = 230-gr. JHP at 1300 (actual 1370). The latter kicked, as Elmer Keith would have put it, like two mules. We thought there was no way a steady diet of that could be good for either your gun or your hand. After shooting the rompin’, stompin’ Rowland, our opinion is that the brake is mandatory.
The G460A did not work in our gun at all. We had massive failures to feed with the blunt, truncated-cone-shaped Nosler. Every round jammed hard into the barrel opening on feeding, and tied up the gun. We were unable to shoot enough of this for accuracy purposes, abandoning it as thoroughly unsuitable for this test gun, so that information is missing from our test results.
The second load listed, G460B, fed and functioned almost perfectly (one failure to feed). We tried it double tapping, and got completely controllable results. We found we could shoot the .460 Rowland Fisher/Norinco as fast and as accurately as we could with .45 ACP loads, thanks to the excellent Clark muzzle brake. The brake seemed to grab the gun in mid-recoil and pull it back down. This was most noticeable with the 230-grain load. Muzzle climb with the hottest .460 Rowland ammo was thus much less than with the .400 Cor-Bon, though the .460 stung our hands, especially the 230-grain load. We thought the 185-grain load was more controllable than any .400 Cor-Bon load. Accuracy for the two tested loads was in the 2.5- to 3.5-inches range, with the heavier bullets striking about 5 inches higher than .45 ACP loads from the same gun. Our test gun showed the first-shot-out syndrome noticeable, the first shot landing here and the next four landing over there. The four might go 1.5 to 2 inches, not at all bad.
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So these two drop-in conversions work, but do you need ‘em? The .460 Rowland offered lots of power and high velocity with heavy .45-caliber bullets, but with much higher pressure. And that heavy spring won’t get cycled by normal .45 ACP loads, which can be safely fired in the .460 chamber. The .400 Cor-Bon offered a less bulky gun, but smaller bullets, harder control and just about as much muzzle blast as the Rowland. One of these two drop-in setups might be for you, but all of us who tried these three would overwhelmingly pick the .50 GI if we wanted more power in a 1911 than the .45 ACP offers.
• Guncrafter Industries Model No. 1 .50 GI, $2895. Our Pick. The .45 ACP is by no means the final answer of the self-defense world, but the .50 GI may well be. It does much more than the .45 ACP can do. There is, we believe, a definite advantage to the .50 GI’s big, heavy bullets, and it’s presented in a superb package. All who have tried the .50 GI think it makes good sense. We think Guncrafter Industries’ headman Alex Zimmerman is onto something with his .50 GI.
• Storm Lake (Machine Solutions) .400 Cor-Bon Drop-In Barrel, $130. Don’t Buy. There was nothing wrong with the barrel, just the caliber. Accuracy with the 165-grain JHP load (our first choice) was more than acceptable, five-shot groups running about 2 inches at 15 yards. All loads struck from 2 inches to 4.5 inches high at 15 yards compared with .45 ACP from the same gun. Heavier bullets struck higher. The poor-feeding 135-grain JHP gave the best group, four shots touching and one more that made it 1.6 inches. The PowRball load was shaky, with one shot landing 6 inches outside of one group, and another group showing two distinct points of impact about 3.5 inches apart. Double-taps were not as easy as with a .45. Speed and bullet placement were both down. Muzzle blast was considerable from all loads. One can perhaps get used to that, but we all felt the .50 GI was much easier to shoot, slow or fast, than the .400 Cor-Bon. We thought the .400 was well worth a look for those who want lighter bullets at otherwise unreachable velocities from the 1911. One of our empties had a pierced primer (small pistol), and though the gun never gave a stutter, we never like pierced primers. Is Cor-Bon asking too much from these loads? We didn’t like the blast and recoil of the .400 Cor-Bon. The loads didn’t offer much but velocity, and some of us are not great fans of velocity at the expense of bullet weight. We all thought that self-defenders would be better served with the .50 GI.
• .460 Rowland Clark Conversion Kit, $275. Conditional Buy. The .460 Rowland was thoroughly workable, delivering much more power than the .45 ACP or the .400 Cor-Bon, and maybe even more real power than the .50 GI, though that is questionable if you get away from the calculator and into the real world. For those who want a simple conversion that offers far more power from a slightly larger package than the normal 1911, the Rowland might just be for you. Clark did a marvelous job, we thought, on this package. But does it make sense to try to turn a 1911 into a .44 Magnum? We don’t think so. We think there are better options, like, say, a .44 Magnum revolver. Our test crew declared we would not own one, but that doesn’t mean the Rowland’s not perfect for you. Be aware that continued use can’t do your 1911 any good in the long haul. Performance costs are not always right up front, nor always obvious.
I realize this article is now 15 years old, but I think the following is still a fair comment
Using a NORINCO 1911 for a drop in barrel conversion would not be my first choice. Norincos can be different in a number of respects. Try changing the sear for a standard G.I. sear and you may see what I mean. There are differences, the Chinese NORINCO is not identical to the Colt or G.I. specs for a 1911.
Muzzle blast will always be higher in super sonic loads. .45 ACP and 50 G.I. are both quite sub-sonic, meaning less muzzle blast and slower recoil. Try a .45 Super with 185 grain JHP loaded to 1100+ fps and you’ll see immediately what I’m saying, in the same gun. It will be very apparent. Don’t forget to use a 20+ lb recoil spring and a HD firing pin spring.
I don’t think the 400 Cor-Bon really got a fair shake. This is typically handloaded and I strongly suspect that aficionados of the 400 C-B are getting much better, more appreciated results. The SLM barrels I’ve installed needed a lot of fitting and I no longer will even bother with them because they are so finicky to fit.
The above article might have been written by someone who writes about guns for a living, but it was certainly not written by someone who knows guns, and certainly not ballistics. Granted a lot has changed in the 15 years since this was written and the three caliber conversions have already worked themselves out. The .400 Corbon is pretty close to gone due to poor function – as noted in the article, and rather lack-luster performance for all the investment of time and effort. About the time this article was written I was thigh-deep in building my own Corbon complete with loading my own ammo. Reliable chambering was just not in the cartridge’s behavior – at least not with the 1911 style feed characteristics. The combination of bottleneck case and first-round “stack gap” causes the first round to be slammed hard into the frame “ramp” which is an almost head-on collision. Then there is the fact that the .400 Corbon only really stands out with lighter bullets. In the end the “right answer” was to go with the straight-wall 10mm.
Then the completely over-hyped, near pointless .50 “Guncrafter” round has also turned out to be nothing more than a rich-dood’s plaything. As with so many custom conversions, the company hawking the .50 GC came to market with intent to gouge the consumer, reducing the value of an already questionable conversion. See, what the writer of the article doesn’t seem to grasp is that we use the derived numerical value called “kinetic energy” as a means of determining the power of a bullet, but also comparison of power across different calibers. The .50 GC was and still is a gimmick. It barely makes 500 lb-ft of KE, and the over-sized slug is “rolling” out the barrel even slower than does the .45 ACP. As a result the blunt .50 caliber bullet has poor penetration due to it’s massive surface area. A 275 grain .50 bullet isn’t enough heavier than a 255 grain .451″ bullet for organic creatures to notice or care. The .50 GC takes all the least desirable aspects of the .45 ACP and magnifies them while giving nothing of practical value…other than rich-dood bragging rights for those stupid enough to by one.
The smarmy comment about those wanting .44 magnum power should probably just buy one completely – and I suspect deliberately seeks to obfuscate the rationale behind the .460 Rowland. I guess Johnny Rowland didn’t start out trying to gouge deep enough to make gun-raggers happy, and there is the fact that it’s power resides dead-squarely IN the .44 magnum’s actual, real-world, chronographed, standard pressure wheelhouse…that REALLY pisses off the gun snobs! How DARE anyone suggest another caliber – especially one designed for the 1911 is on the same level! Well, of the guns and calibers presented here, the Rowland in 2020 is still alive and well, and continuing to grow as more shooters discover it really DOES replace the antiquated six-shot .44 magnum wheelgun for field carry!
A 1911 fitted with conversion weighs about the same as a short-barrel .44 magnum revolver – not including the high-dollar exotic materials versions which only magnify all the negatives of magnum revolvers. When talking muzzle brakes, everyone who has ever lined up behind a Barret .50 BMG “rifle” understands fully how absolutely vital and effective is that thing hanging off the barrel. Johnny Rowland’s real “invention” wasn’t the cartridge that bears his name so much as the “system” he came up with to handle it! Muzzle brakes can easily reduce felt recoil by over 70%, and if size were no object, a muzzle brake could reduce “kick” to zero! In the case of the 1911, by mounting the brake onto the barrel, when the bullet passes through the brake, expanding gasses impinge on the interior “flats” and become directed upward through the large ports. The net effect is gas and thus energy is diverted lateral to the gas stream, as well as used to physically “shove” the barrel forward. The slide, being locked to the barrel, is also locked forward. The end result is a longer delay before unlocking, with less energy imparted into the reciprocating mass. The effect is so profound that the .460 Rowland can get away with a 24 pound recoil spring – or less. Mine currently has a 20/40 pound dual, flat-wound coil that wasn’t available in 2005. Combined with the superior ergonomics of the autoloader platform, this makes the .44 magnum equal .460 Rowland have astoundingly mild recoil! The first time I touched off the .460 Rowland in my Glock long slide conversion I had to “remember” to pay attention to the kick to notice if it had any! When I built my first 1911 conversion, I was half-way through testing a sequence of hand loads before I realized I hadn’t noticed any recoil! I keep reading comments all over the internet about the heavy recoil and clearly those making such pronouncements are revealing they haven’t actually fired a .460 Rowland!
Thankfully, the merits of the caliber, being highlighted in videos across the internet, have managed to counter the negatively slanted reporting of so many gun-rag writers! Like many I had no interest in the .460 Rowland, because like many, not knowing anything about it, I had no idea what I was missing. I thought the only way to have “real” power was the same tired, six shot wheelgun of whatever caliber. I’m not sure when I first “noticed” the .460 Rowland, but after I put together a Glock longslide version and saw 1,722 fps AVERAGE roll up on the chronograph when firing Underwood’s 185 grain load I was hooked! By direct comparison I chronographed some PMC 180 grain .44 magnum from my Desert Eagle at a mere 1,584 fps…which I formerly considered pretty fast, but clearly the 34 ounce Glock .460 Rowland conversion beat that .44 magnum factory load with room to spare! Also, the Glock AND the 1911 conversion are far more ergonomic than the monster Desert Eagle and weight about half as much! After that I had no qualms selling off the Desert Eagle. Even though I still own several .44 magnum revolvers, they pretty much stay indoors while one or the other of my .460 Rowland conversions go with me out into the wilderness. I prefer the ergonomics of the 1911 an the hammer-fired, crisp trigger with thumb safety to the Glock even though the Glock tips the scales a good 10 ounces lighter!
Clark still offers their conversion – which is what I have, and yes it is unforgiving of certain blunt nose shapes as the cost of having full chamber support, but part of that equation lies in the magazines chosen. With the 1911 I found Chip McCormick Powermags to be the ticket for sustained reliable function – not that any of my conversions have ever had a problem with reliability.
Because the bullets are moving so much faster than .45 ACP, conventional hollowpoint bullets made for the .45 auto tend to expand dramatically and limit penetration. A better approach is to go with FMJ FP design which impart tremendous shock on impact due to traveling well above the speed of sound. At 1,600 fps, even a round nose 185 grain .451″ bullet creates an enormous temporary expansion cavity ALL the way through the testing medium! Highly aerodynamic rifle bullets need to expand on impact due to having such a narrow shock cone, but blunt pistol bullets – even and especially .451″ style, not being designed for supersonic flight, when driven well above the speed of sound, form a very wide shock cone and really don’t need to expand at all to be highly effective at putting organic creatures down. Another excellent choice for the .460 Rowland are the plated or jacketed SWC style .451″ bullets because they develop the largest, most abrupt shock cone of all.
In the field my 1911 conversion has a 10 round CM PM in place which is 10 shots versus six in a revolver, and being instantly ready to reload. The .460 conversion is also highly controllable and can be fired as fast as a non-compensated 1911 – which is pretty fast!
Huh… the $3000 purpose-built gun was better than a cheap-o gun with an inexpensive drop-in barrel? I’m shocked. What an awesome, well thought-out comparison.
I absolutely love my Rowland and with the compensator, it doesn’t feel like it kicks as hard as my 45acp without a compensator. I have also been shooting 45acp for a lot of target practice and haven’t had a single failure to feed issue even with the 460 Rowland spring. I absolutely love this beast and it shoots amazingly well. I purchased a heavy, all metal 1911 to do the conversion and I don’t think it will have any wear and tear issued.
Thanks!!