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Recoil springs and accuracy issues


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So i have a used Limcat SteelCat that im having issues with. Accuracy is pretty terrible. When i received the gun i slapped an RTS2 on and a Tevo sports thumb rest. From there i decided to zero it and what i was getting was 3-4” groups at best at 18 yards(im zeroing for steel challenge). Loads in question were 124gr Bayou .356’s with 2.8gr of TG, some 105pf type loads. They cycles find no issues. These loads would punch the same hole out in any other gun. The recoil spring inside was unknown but it felt light possibly an 8 maybe. Previous owner is claiming 4-5” groups at 50yards.
 

So i decided to toss a 7lb spring inside to see how it cycled, no issues. But i wasnt satisfied with the groupings. Still using the 7lb spring i shot a bunch of different types of ammo. 
Factory 124gr Nato

Factory 115gr Blaser

100gr Berrys, 3.5gr TG, previous steel load

100gr Berrys, 4.4gr TG, pcc load

124gr Bayou, 3.5gr TG 

 

The groups opened up abysmally and super inconsistent. Off a rest perfectly stable. There were no comp baffle strikes anywhere. Barrels rifling looks good. The fit of the gun however is not tight. By that i mean there is a little play in the slide to frame fit and the hole where the slide stop goes into the barrel link is slightly oval and no perfectly round. 
 

So my question is, since the gun kinda loose, could too light of a recoil spring cause lockup issues? I never thought this could be a thing until i read about a guy whos Atlas after 1500 s#!t the accuracy bed when he started putting light recoil springs inside and was fixed when he put a heavier one back in. But this is a loose fit steel challenge gun shooting way below sub minor. 
 

also here is a picture for reference. Also 2 of the 124 nato was off to the left outside the perf but theres 4 on paper
mUP3o1e.jpg

 

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You need to look at your ammo first.  Go back to original spring and try several different bullet types, ie jacketed, plated, coated.  As long as it’s safe and functions, charge weight in 9mm means little regarding accuracy at 18yrds.  
 

The amount of crimp you’re using is probably the reason for inconsistency.  
 

spring weights will definitely affect groups but in general it’ll result in a flyer from a tight group, vs an overall shotgun pattern.

 

its 99.9% a bullet/crimp/swage issue with the ammo in a gun like that

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18 minutes ago, drewbeck said:

You need to look at your ammo first.  Go back to original spring and try several different bullet types, ie jacketed, plated, coated.  As long as it’s safe and functions, charge weight in 9mm means little regarding accuracy at 18yrds.  
 

The amount of crimp you’re using is probably the reason for inconsistency.  
 

spring weights will definitely affect groups but in general it’ll result in a flyer from a tight group, vs an overall shotgun pattern.

 

its 99.9% a bullet/crimp/swage issue with the ammo in a gun like that

Well thats kinda why i tried 2 different factory rounds. Granted they were all some form of Round Nose, it wasnt much different. Ill Play with the crimp a little but would the gun make that much of a difference considering the same exact ammo and crimp shot perfect out of ANY other gun i tried it from?

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1 hour ago, drewbeck said:

You need to look at your ammo first.  Go back to original spring and try several different bullet types, ie jacketed, plated, coated.  As long as it’s safe and functions, charge weight in 9mm means little regarding accuracy at 18yrds.  
 

The amount of crimp you’re using is probably the reason for inconsistency.  
 

spring weights will definitely affect groups but in general it’ll result in a flyer from a tight group, vs an overall shotgun pattern.

 

its 99.9% a bullet/crimp/swage issue with the ammo in a gun like that

So i just adjusted the crimp so that it doesnt even leave a mark or anything on the bullet if pulled and still gauges and feeds fine. I tried a longer OAL out to 1.160 and i also tried a 9lb spring and even the original spring. Nothing changed at all. 

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46 minutes ago, Bravo_Victor said:

So i just adjusted the crimp so that it doesnt even leave a mark or anything on the bullet if pulled and still gauges and feeds fine. I tried a longer OAL out to 1.160 and i also tried a 9lb spring and even the original spring. Nothing changed at all. 

Why not reach out to Limcat? They will go through the entire gun if you send it to them. 

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Hello, at 18 yards that is not very good groups. Check to make sure your dot setup is all tight. Check to make sure your bullets are not contacting the comp. Also check to see how loose the link is on the pins. Just somethings to check. Thanks, Eric

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First of all, why did you buy that gun if you intended to shoot mouse fart loads in it?  You would have been much better off shooting your 105 PF load in an uncompensated gun.  For example, a 115gr @ 109 PF barely moves the gun when shot in my XD 4" 9mm.

 

Second, the good grouping of the Nato 124 ammo (hot) shows it is less likely to be all about the gun.  You have some good suggestions above.

 

Here is how I would approach your problem.  The first thing I would do is clean the gun thoroughly, especially the bore and comp.  You may have to dig a lot of crap out of the comp chambers.  Make sure you get down to steel.  Also scrape everything off the baffles, front and rear.  Take a U size drill (.368") and push the back end through the front of the comp.  Did it go back to the rifling with no resistance?  If not, you have some reaming to do.  Ream to a minimum of .369".

 

When you cleaned the barrel was there any resistance?  Double up on the swabs so you get a really tight fit in the bore.  If there is any resistance at all, lap your barrel.

 

Remove the comp and carefully clean the crap around the crown.  Press down on the top of the barrel back towards the hood.  Any downward movement?  If so you need a longer link.  BTW, it is perfectly acceptable to oval the hole in the link pin to get proper lockup.  This is often done with a #3 link if everything else is not absolutely perfect.  If a #4 link is too long you have no other choice, or go to one of Matt Cheely's 'in-between' links.

 

Put Dykem or magic marker on the bottom lugs.  Reassemble and rack the slide 20-30 times.  Pull it all the way to the rear and let it go.  Your fingers should slide off the rear of the slide so you are not softening the closing in any way.  Has the marking rubbed off the lower legs.  If yes, good.  If not, remedy.

 

Once you have done all of this, and corrected any deficiencies, you can eliminate the gun as a source of the problem.  A buddy of mine shot a used Open gun for USPSA and SCSA.  He cracked his slide.  He asked me to fit a new one.  I took the gun apart, cleaned it and measured.  The frame rails measured .750".  The slide ways were .755".  By any definition it was loose.  However, since everything locked up correctly, he did fine with it.

 

Now, fix your ammo choice.  You really should not be shooting coated or FMJ bullets in a compensated gun, ESPECIALLY not with TG as the propellant.  TG burns a lot hotter than other propellants and that exacerbates the problem.  It is also dirty.  Most of the Open SCSA shooters I know run loads in the 140 to 155 PF range using powders like WAC or Silhouette.  I happen to run 3N38 because I have gobs of it and I can't make major with it.  So I use it up for minor loads.  I'm at 144 PF with 124 plated.  I'm going to bump it up a little.  Pick a nice plated bullet of JHP and stick with it.  The idea is to get the gun to shoot soft and flat.  Otherwise, why did you but a comp?

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zzt has provided a lot of solid advice and a logical approach to tacking the issue.

 

The only thing that is missing from it is considering the twist rate of the barrel rifling vs the velocity of the ammo you are using. Most open guns are setup with a slower twist rate rifling because major power factor velocity ammo requires less twist rate. Normal 130 - 145 minor power factor ammo requires a faster twist rate and sub minor ammo requires an even faster twist rate. The twist rate of the barrel determines the RPM of the bullet and every bullet has an RPM sweet spot that will produce stability of the projectile in flight.

 

Most competition shooters who reload their ammo have a hyper focus on "Soft Shooting" ammo and don't verify that their Mouse Fart ammo still maintains accuracy. They fail to realize that bullet size, weight, velocity and RPM all need to be in harmony in order to maintain accuracy. That "Harmony" may require a final Power Factor that doesn't produce the Mouse Fart felt recoil that you were striving for.

 

If I was troubleshooting this issue, I would do some accuracy testing using legit Major Power Factor (170+ PF) ammo in a range of bullet weights (115gr, 121gr, 124gr). If the accuracy tightens up using Major PF ammo then the root cause of the issue is likely that the twist rate of the rifling is too slow for Minor/Sub Minor ammo.

Edited by CHA-LEE
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I also want to point out that light recoil springs will expose inconsistent barrel lockup and slide to frame fit issues. If the barrel lockup is poor, or the slide to frame fit is really sloppy then you need a recoil spring heavy enough to at least produce a consistent resetting point for these parts when the slide snaps back into the full forward position.

 

To eliminate or minimize the lock up/slop issues adding to the accuracy issues I would suggest using a recoil spring that is at least 4 - 5 lbs heavier than "Normal" in it. You are trying to use a 7 or 8lb recoil spring, try an 11 - 12lb recoil spring while testing different ammo. If the accuracy dramatically improves when using a heavier recoil spring then you know the issue is due to barrel lockup or slide to frame fit sloppiness.

 

When people want to use sub minor ammo it usually requires a really light recoil spring to cycle reliably. This is a double edge sword because a really light recoil spring will expose mechanical lockup issues. You may have to accept the fact that the current "Sloppiness" of the gun may require a minimum weight recoil spring that is much heavier than you expect. It may be heavy enough to not cycle sub minor ammo reliably which means that you can't use sub minor ammo. 

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Thanks everyone i will check all that out after work. Just fyi these loads are what i had on hand from shooting an uncomped Open gun (czechmate), Production, limited and CO, not necessarily what i planned on shooting. Just wanted to see if the gun cycled which it did and see how they shot. I havnt tried my 173pf major ammo yet bc i wasnt sure how the gun would take it considering its built as a steel gun. But the factory ammo performed worse. The 124 nato you see didnt show the other few rounds that were way off. I also shot later in with the Nato and it was just about as bad as the 2.8gr with 124gr. I know the comp is pointless but finding an uncomped frame mounted 2011 isnt something you can really find. 

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1 hour ago, Bravo_Victor said:

Thanks everyone i will check all that out after work. Just fyi these loads are what i had on hand from shooting an uncomped Open gun (czechmate), Production, limited and CO, not necessarily what i planned on shooting. Just wanted to see if the gun cycled which it did and see how they shot. I havnt tried my 173pf major ammo yet bc i wasnt sure how the gun would take it considering its built as a steel gun. But the factory ammo performed worse. The 124 nato you see didnt show the other few rounds that were way off. I also shot later in with the Nato and it was just about as bad as the 2.8gr with 124gr. I know the comp is pointless but finding an uncomped frame mounted 2011 isnt something you can really find. 

 

I don't know how much the Limcat slide weighs, but I wouldn't shoot 173 PF loads in it at all.  However, if you go to an 11 or 12 lb recoils spring it should be okay.  I don't see why you just don't load up a dozen rounds with your major powder and bullet to about 150 PF.  My 1911 Open steel gun has a 1:16 twist and runs 124s at 140 PF just fine, and it is accurate.  That's as low as I can go and still have the slide cycle.  I used 7 lb. for the 140 load, 8 lb. for the 144 load and I switch to a 12 lb. when I want to shoot 169 PF loads.

 

You can drill and tap any dust cover for a frame mount.  If you want to continue shooting coated bullets, buy another barrel and fit it.  I did just that.  My home club does not allow poppels or comps in their outlaw matches.  So I bought a Barsto 9mm bull barrel and fitted it.  Now I can use the same gun with my 144 PF loads in the comp'd barrel and my PCC loads in the bull barrel.  They both shoot to the same POI.  I won the Club Championship using that gun with the bull barrel.  Next year I may even shoot it in the bullseye leg.  

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4 hours ago, zzt said:

 Now, fix your ammo choice.  You really should not be shooting coated or FMJ bullets in a compensated gun, ESPECIALLY not with TG as the propellant.  TG burns a lot hotter than other propellants and that exacerbates the problem.  It is also dirty.  Most of the Open SCSA shooters I know run loads in the 140 to 155 PF range using powders like WAC or Silhouette.  I happen to run 3N38 because I have gobs of it and I can't make major with it.  So I use it up for minor loads.  I'm at 144 PF with 124 plated.  I'm going to bump it up a little.  Pick a nice plated bullet of JHP and stick with it.  The idea is to get the gun to shoot soft and flat.  Otherwise, why did you but a comp?

I know TG burns hot but i just dont see it making too much of an issue with 2.8gr. Im even using 4.4gr with 100gr Plated Berrys in my PCC going 1300fps and they punch the same hole out at 35-40 yards. I know alot of people using BB as well i comped guns shooting 173-175pf that have no issues besides having to clean the s#!t out of comps so often but their accuracy is fine. Im gonna load up some JHP around 145pf and see how that runs with AA7 or HS-6. 

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6 minutes ago, zzt said:

 

I don't know how much the Limcat slide weighs, but I wouldn't shoot 173 PF loads in it at all.  However, if you go to an 11 or 12 lb recoils spring it should be okay.  I don't see why you just don't load up a dozen rounds with your major powder and bullet to about 150 PF.  My 1911 Open steel gun has a 1:16 twist and runs 124s at 140 PF just fine, and it is accurate.  That's as low as I can go and still have the slide cycle.  I used 7 lb. for the 140 load, 8 lb. for the 144 load and I switch to a 12 lb. when I want to shoot 169 PF loads.

 

You can drill and tap any dust cover for a frame mount.  If you want to continue shooting coated bullets, buy another barrel and fit it.  I did just that.  My home club does not allow poppels or comps in their outlaw matches.  So I bought a Barsto 9mm bull barrel and fitted it.  Now I can use the same gun with my 144 PF loads in the comp'd barrel and my PCC loads in the bull barrel.  They both shoot to the same POI.  I won the Club Championship using that gun with the bull barrel.  Next year I may even shoot it in the bullseye leg.  

Thats what my next step is as stated above. Gonna load 145ish with my major powder and bullets and see how it runs. If all else fails with the above advice, i will see about having Limcat take a look at it

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Barrel lock up causes accuracy issues, but the there are two other things that are much worse.  1.  Bullets colliding with the comp, if this is happening you will see a shiny spot on the edges of the bore holes in the comp.  However I usually shoot the next no shoot in the array when this happens.  2.  Barrel to slide, or if cone comp the cone to slide fit, any slack here and you will be spraying a wide path.  

 

Loads and bullets as someone said don't make a lot of difference, well I'll say this ain't horse shoes.  Tite Group is my least favorite powder for 9 mm, but I happen to love them bayou bullets, just not in my open gun, although I have shot thousands of them at 1400+ fps, I just keep the drimmel handy to gouge the lead out of the comp.   I don't spend a lot of effort on a minor steel load but I use a powder that provides some gas to the comp.  Like AutoComp at 5.5gr to 5.8gr with 124gr JHP.  If you can shoot an 8" group at 35 yards you should be able to hit all the steel in a steel match, but in a USPSA match those peskie poppers will eat your tamale.  If factory ammo isn't working its probably not ammo.

 

Ok so everything checks out, then what, maybe it is like my old 30-06 deer rifle, when old Ned strolled up with his majestic horns I missed him 3 times, took that rifle to the smith and he did every thing from glass beading to free floating and wallet draining, still didn't work.  On a hunch I got a new Scope, Ned's head is in the Den.  Maybe you got dot float. 

 

Ooh and if the slide is real loose on the frame AccuRail, I had one done and it was a tack driver after, I sold it right away if it was accurate and I wasn't it had to go.

 

 

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11 minutes ago, CocoBolo said:

Barrel lock up causes accuracy issues, but the there are two other things that are much worse.  1.  Bullets colliding with the comp, if this is happening you will see a shiny spot on the edges of the bore holes in the comp.  However I usually shoot the next no shoot in the array when this happens.  2.  Barrel to slide, or if cone comp the cone to slide fit, any slack here and you will be spraying a wide path.  

 

Loads and bullets as someone said don't make a lot of difference, well I'll say this ain't horse shoes.  Tite Group is my least favorite powder for 9 mm, but I happen to love them bayou bullets, just not in my open gun, although I have shot thousands of them at 1400+ fps, I just keep the drimmel handy to gouge the lead out of the comp.   I don't spend a lot of effort on a minor steel load but I use a powder that provides some gas to the comp.  Like AutoComp at 5.5gr to 5.8gr with 124gr JHP.  If you can shoot an 8" group at 35 yards you should be able to hit all the steel in a steel match, but in a USPSA match those peskie poppers will eat your tamale.  If factory ammo isn't working its probably not ammo.

 

Ok so everything checks out, then what, maybe it is like my old 30-06 deer rifle, when old Ned strolled up with his majestic horns I missed him 3 times, took that rifle to the smith and he did every thing from glass beading to free floating and wallet draining, still didn't work.  On a hunch I got a new Scope, Ned's head is in the Den.  Maybe you got dot float. 

 

Ooh and if the slide is real loose on the frame AccuRail, I had one done and it was a tack driver after, I sold it right away if it was accurate and I wasn't it had to go.

 

 

Ive experienced baffle strikes with my Akai and that wasnt pleasant. So far from what i can tell im not getting any with the Limcat. The slide isnt REAL loose but if you shake the gun hard you can feel a slight wiggle or if you grab the slide and push it around you can see it slightly. However there is some play in the barrel if the slide is forward if you press DOWN on the comp. You can see theres some space in between the barrel and the bushing that appears to be unremovable. Im going to try and take a video or something tonight 

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Try putting a heavy recoil spring in the gun for a test. The gun may not cycle, and that's OK. Make it a single shot, if necessiary. Shoot for a group, and see if it changes anything. With too light of a recoil spring, your gun can unlock too early, or not lock up properly, which can cause a host of accuracy issues. I am not saying that this is your problem, but you can eliminate it as a cause, by doing this.

Edited by GBertolet
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1 minute ago, GBertolet said:

Try putting a heavy recoil spring in the gun for a test. The gun may not cycle, and that's OK. Make it a single shot, if necessiary. Shoot for a group, and see if it changes anything. With too light of a recoil spring, your gun can unlock too early, which can cause a host of accuracy issues. I am not saying that this is your problem, but you can eliminate it as a cause, by doing this.

I just bought some 10,11,12,13 pound springs to test that theory

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On 3/5/2021 at 4:41 AM, Bravo_Victor said:

So i have a used Limcat SteelCat that im having issues with. Accuracy is pretty terrible. When i received the gun i slapped an RTS2 on and a Tevo sports thumb rest. From there i decided to zero it and what i was getting was 3-4” groups at best at 18 yards

I can't help thinking it could be the RTS2 that you replaced is the culprint here? Maybe reverse to the original dot and test for accuracy issues?

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1 hour ago, Grendel said:

I can't help thinking it could be the RTS2 that you replaced is the culprint here? Maybe reverse to the original dot and test for accuracy issues?

Original dot was a RTS2 that came with it that i put on my pcc as a 45° optic. If the recoil spring test doesnt pan out i could always throw a Cmore slide ride and mount on that i have laying around and try that. 

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Just to clarify a loose barrel bushing (aka when the gun is locked up and the barrel wiggles in the end of the slide) if it is enough you can feel it you need to have a smith check it out and correct if he/she/it recommends it.

 

Lock up is evaluated with the gun closed (locked up) push down on the barrel hood if it moves it needs to be fixed.  Slide slop isn't that important until it is, meaning it can be loose but when it gets too loose then its a problem. If the barrel bushing is tight and the hood doesn't move it should be accurate enough to shoot in matches.  I had one that shot well, you could hold it and rotate the wrist left to right and hear it rattle but it had good lockup and the bushing was tight.  It only had about 100,000 round down the tube.

 

Recoil springs, with light loads I've run 7, 8# springs but those don't always work out because you run into feed issues, I'd recommend a good 10# spring, if the gun works well with that you can then work your way down till it stops working and move one up.

 

Just like when I was racing stock cars, you make one change and only one change go back out and time/test it.   Changes to loads changes to the gun I always evaluate those with a timer, establish a baseline then make the change and see if you are faster. Some times it feels good and makes you slower.

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