trouble shooting infinity open gun

[sliphorn]

I need suggestions. I have a custom open gun built on a SV infinity frame, Springield slide, purchased used. (mistake.) Accuracy has been a big problem from the first. 25 yd groups tended to be at least 6+ inches or worse, with different loads shooting to extremely different points. I had a good gunsmith take a look and he made some tweaks, refitted barrel, but not much improvement, so he replaced the barrel with a new STI tru-bore. Still not much improvement so we sent it in for Accurail job since slide was a bit loose. Still no significant improvement so sent it back to the Accu-rail smith who notice a crack in the comp, which he welded and reamed for more bullet clearance, still with little improvement. Sent the gun to a 3rd smith who replaced the barrel and comp again. I have now developed two loads that work half way decently for steel using 95 and 100 grain plated round nose bullets going into 1" or less at 25 FEET, but everything else is 3" or bigger at 25 FEET, (often won't stay on paper at 25 yards) always with the first shot very low and left and the rest forming a loose but sometimes acceptable group. Does anyone have any ideas?

[lcs]

I need suggestions. I have a custom open gun built on a SV infinity frame, Springield slide, purchased used. (mistake.) Accuracy has been a big problem from the first. 25 yd groups tended to be at least 6+ inches or worse, with different loads shooting to extremely different points. I had a good gunsmith take a look and he made some tweaks, refitted barrel, but not much improvement, so he replaced the barrel with a new STI tru-bore. Still not much improvement so we sent it in for Accurail job since slide was a bit loose. Still no significant improvement so sent it back to the Accu-rail smith who notice a crack in the comp, which he welded and reamed for more bullet clearance, still with little improvement. Sent the gun to a 3rd smith who replaced the barrel and comp again. I have now developed two loads that work half way decently for steel using 95 and 100 grain plated round nose bullets going into 1" or less at 25 FEET, but everything else is 3" or bigger at 25 FEET, (often won't stay on paper at 25 yards) always with the first shot very low and left and the rest forming a loose but sometimes acceptable group. Does anyone have any ideas?

You indicated "plated" bullets. You might be over crimping, which can destroy accuracy. I would suggest you try a different bullet and powder. Many times accuracy is greatly affected by the load rather than the gun. Hard to believe the gun is the problem after being rebarrled. My accrailed gun has awesome accuracy.

[BBoyle]

How experienced are you with reloading? It is possible that you are loading a bad combination if you have had that many smiths look at it. As far as 1st shot not hitting where everything else does when the gun is fired, that is pretty common. Get some good to high quality HPs from zero, montano gold, hornady, etc. and see how they shoot.

Are you trying to shoot the groups off hand or are you using a rest or sandbags? When testing for absolute accuracy I always use a rest or bag to help stabilize the pistol.

What about the scope and mount? If it is a C-More look for little cracks where the advustment and tension screws are. If they are overtightened you will crack the frame and lose zero entirely. If this is the case it is a cheap easy fix, just send it to C-More and for about 60 bucks it will be fixed.

How secure is the mount itself?

If it is a tube sight start looking into issues with that as well....try taking the scope off and put it on another gun. Sight it in and see if the scope holds zero. I do not know any other way to troubleshoot a tube scope besides that.

I hope you get everything sorted out.

Brian

[CocoBolo]

Plated bullets are famous for hitting the popper when pointing at the paper. Not withstanding that, I would replace the C-More. This sounds like the opposite of my dad's deer rifle, which I'll say fustrated me some for a while. First shot always dead on in the bulls eye, and subsequent shots somewhere in orbit. Problem was the cross hairs in the scope were jumping, then when you let it rest a bit they returned to where they were supposted to be. If you put a new true bore in it and accu-r-rail then its definately none of those things so looks elsewhere, aka the C-More.

Doug Jones did an acc-u-rail on an SVI I had and it was absolutely fantasticly accurate, the slide to frame fit was tighter than dick's hat band. The gun shoots <1" at 25 yards, usging good bullets like Zero or MTG 125gr. The barrel in that gun was worn out and it had a cracked comp but bullets were not hitting the comp, you can tell when they do either by looking for little flakes of copper in the comp or by the way it shoots. It stil whot very well, the new owner replaced the barrel, comp, C-More and has an awesome gun. Before Doug worked his magic the slide was so loose when you leaned the gun side to side you could hear the clunks.

[sliphorn]

Thanks for the suggestions, but been there, done that. I have many years of reloading experience. The plated 95 and 200 grainers are the only ones that work. I have also tried Golden sabers,both 124 and 147 grain, Winchestwer HP 115, Berry 124 HP and RN, Rainier 124 and 115 Rn and Hp, Factory Win and Remington 115 Hp and RN. Powders include Auto Comp, HP 38, Win 231, Clays HS 6 and Tite group. Primers CCI and Fed. Many loads that work well in my other guns, including a switch top Springfield single stack comp gun put together by one of the mentioned smiths. I have swithed out the C=More with one from My tweaked Custom shop 657 known to shoot very accurately. Sight from that gun didn't help, sight taken off the SV worked great on the 657. Doug Jones did the Accurail job and worked on the Tru-bor barrel, welding the cracked comp and reaming it. So I have concluded it's not the loads and not the sight. It's not just big groups, but the fact that it is always shot #1 that is low left with the rest mostly clustered more tightly high right that might be the key. Again, the light plated bullets are the only successful load so far, other loads are good in all my other guns.

[Hi-Power Jack]

Have you made sure all your screws are tight?

I had a TruBor lose its point of impact because

the grip screws were loose.

[sliphorn]

Thanks for the suggestions, but been there, done that. I have many years of reloading experience. The plated 95 and 200 grainers are the only ones that work. I have also tried Golden sabers,both 124 and 147 grain, Winchestwer HP 115, Berry 124 HP and RN, Rainier 124 and 115 Rn and Hp, Factory Win and Remington 115 Hp and RN. Powders include Auto Comp, HP 38, Win 231, Clays HS 6 and Tite group. Primers CCI and Fed. Many loads that work well in my other guns, including a switch top Springfield single stack comp gun put together by one of the mentioned smiths. I have swithed out the C=More with one from My tweaked Custom shop 657 known to shoot very accurately. Sight from that gun didn't help, sight taken off the SV worked great on the 657. Doug Jones did the Accurail job and worked on the Tru-bor barrel, welding the cracked comp and reaming it. So I have concluded it's not the loads and not the sight. It's not just big groups, but the fact that it is always shot #1 that is low left with the rest mostly clustered more tightly high right that might be the key. Again, the light plated bullets are the only successful load so far, other loads are good in all my other guns.

Also tried Hornay 124 grain Hp, bad results consistent with other bullets.

[Aircooled6racer]

Hello: What is the twist of the barrel you are using now? How tight is the barrel to slide fit? What is the power factor of your major loads? One thing I know is that the Accurail job is giving a good slide/frame fit for sure. Are the bullets hitting the comp? How tight is the chamber? Lots of things to consider. Thanks, Eric

[sliphorn]

Have you made sure all your screws are tight?

I had a TruBor lose its point of impact because

the grip screws were loose.

Everything seems tight.

[Joe4d]

sounds like a frame to slide or barrel fit issue, The first shot is hand cycled after slapping the mag probably raising the rear of the slide, the rest of the shots are being cycled by the gun. Maybe a stronger recoil spring ?

[sliphorn]

Hello: What is the twist of the barrel you are using now? How tight is the barrel to slide fit? What is the power factor of your major loads? One thing I know is that the Accurail job is giving a good slide/frame fit for sure. Are the bullets hitting the comp? How tight is the chamber? Lots of things to consider. Thanks, Eric

Good Ideas. I'm not sure of the twist rate on this one, I will check it out, but this is the first of the three barrels that has shot anything well. Barrel to slide fit is very tight, In fact I put about 500 rounds throug it before I got really reliable function. I can't shoot run and gun because of a disability, so I don't worry about making Major. I wouldn't worry if all I did was shoot paper and clang steel, but I use this as my smallbore pin gun and for reactive steel where I need more power without damaging the steel with high velocity.

[sliphorn]

sounds like a frame to slide or barrel fit issue, The first shot is hand cycled after slapping the mag probably raising the rear of the slide, the rest of the shots are being cycled by the gun. Maybe a stronger recoil spring ?

Everything is very tight re: barrel to slide and slide to frame. I tried goi8ng up in spring rate until the gun stopped functioning. No improvement in pattern resulted.

[Ken Mays]

Start ruling things out.

Take the sight & mount out of the equation by having it shot from a Ransom rest. Shoot different loads in it to rule those out.

[sliphorn]

Start ruling things out.

Take the sight & mount out of the equation by having it shot from a Ransom rest. Shoot different loads in it to rule those out.

Good Ideas. I don't have an insert to fit the Infinity double stack grip, and don't know of one, but I am shooting from a rest. I have tried many, many different load combinations with the same results.

[JakeMartens]

Have you let someone else shoot it, just to make sure that it isn't you?

[sliphorn]

Have you let someone else shoot it, just to make sure that it isn't you?

A bit. Same results. I am having no trouble with any of my other guns, including a custom 40 on a STI 2011 frame that is set up and feels much the same.

[Powder Finger]

With all that's been done to it what is the 1 or 2 things that remain the same from the beginning?

[sliphorn]

With all that's been done to it what is the 1 or 2 things that remain the same from the beginning?

Thanks, that's and interesting thought. Same frame, grip module, and Slide, internals, but with accu-rail done to enhance frame slide fit, which is now very tight I just got done checking grip module to frame fit and looking for cracks, with nothing found. Have put Tru-bor barrel back in and will try again this afternoon.

[L9X25]

You have systematically eliminated the majority of the possible problems and, unless you replaced a bad barrel with another equally bad barrel, I would guess that the scope is the issue. Beg, borrow or steal another scope to try before you pull out any remaining hair that you have.

[Powder Finger]

You have systematically eliminated the majority of the possible problems and, unless you replaced a bad barrel with another equally bad barrel, I would guess that the scope is the issue. Beg, borrow or steal another scope to try before you pull out any remaining hair that you have.

Agree, I don't think your going to get 2 bad barrels. The sight is very probable.

Are you using the new comp or the cracked/welded one?

**************

never mind I guess those are 1 piece barrel/comps

If it were me I would test cheapest/easiest first, and to me that is to take the comp off and shoot it (If thats possible)

**************

Then go to the scope, but no matter the order, just don't loose your head and start doing multiple tests one fix at a time.

I just don't think it's a barrel, I had one with no rifling for 1.5 inches (25,000+ rounds) and it shot better than that.

As Aircool said maybe twist with the light bullets, but I would think it would do well with the Win115JHP.

Also I would get it to group well first then tackle the first shot deal separatly.

Edited March 10, 2011 by Powder Finger

[sliphorn]

You have systematically eliminated the majority of the possible problems and, unless you replaced a bad barrel with another equally bad barrel, I would guess that the scope is the issue. Beg, borrow or steal another scope to try before you pull out any remaining hair that you have.

Agree, I don't think your going to get 2 bad barrels. The sight is very probable.

Are you using the new comp or the cracked/welded one?

**************

never mind I guess those are 1 piece barrel/comps

If it were me I would test cheapest/easiest first, and to me that is to take the comp off and shoot it (If thats possible)

**************

Then go to the scope, but no matter the order, just don't loose your head and start doing multiple tests one fix at a time.

I just don't think it's a barrel, I had one with no rifling for 1.5 inches (25,000+ rounds) and it shot better than that.

As Aircool said maybe twist with the light bullets, but I would think it would do well with the Win115JHP.

Also I would get it to group well first then tackle the first shot deal separatly.

I have traded out the c-more for another of known quality. This gun shot the same, bad. The other gun with the sight from this one on it still shot great. I just got back from trying more loads and changing back to the Tru-bor barrel. Shot like crap. Not just 1 off and the rest in a semblance of a group, but all over the paper. Won"t hold 3 inches at 25 FEET. Going back to the last barrel and the 7# spring. At least that shoots a decent group with the light bullets. I also shot my Springfield single stack with a cheap grip replacement mount and tasco propoint. Shoots MUCH better than this gun. Even beats it running 9mm in the super barrel.

[pjb45]

You may know Bill L at C&S. He took my BHP to Irv to have the barrel fitted. BHPs were noted for having a flier. Now Ralph built the gun and both Ralph and Bill are members of the pistolsmith guild but it was taken to Irv when Bill went out to visit him. It does not have a flier tendency now.

I mention this because, you gunsmith(s) may be excellent smiths but.....it really could be the barrel to slide fit is the problem. There may be some quark in the slide that causes the problem.

Have you called Brandon at SV about the problem. He is a pretty nice guy and might have some suggestions.

IMO the top SV gunsmith is Don at Kodiak Precision. You might call him although he is out shoot crows more often than not lately.

My next two suggestions would be Matt M and Bob L. Derek is excellent also.

Edited March 10, 2011 by pjb45

[Aircooled6racer]

Hello: Buy some Winchester white box and see how it shoots. That takes the reloads out of it and may get you closer to what is going on. Thanks, Eric

[Walküre]

You have systematically eliminated the majority of the possible problems and, unless you replaced a bad barrel with another equally bad barrel, I would guess that the scope is the issue. Beg, borrow or steal another scope to try before you pull out any remaining hair that you have.

Actually, I've got another idea - one element that hasn't been eliminated. The OP said he already tried swapping scopes... but what about the mount itself? It could still be a bad mount affecting the C-More, which would explain why swapping scopes didn't make any difference.

[R.Elliott]

If you are shooting an AET coated barrel you will likely never get it to shoot a decent group with plated bullets. Rifling too sharp/too deep and bullet plating not thick enough/cores too soft to withstand the transition through the bore.