Trouble with a Ruger Mark IV customized

[Danno919]

Hey all, I just picked up a Ruger Mark IV Lite, and it's had a LOT of customization done to it, mostly Tandemkross stuff, including the clips. Looks like maybe the previous owner did some competitions with it.

Anyway, I took it to the range the other day, and noticed that after the last round was fired, the bolt didn't stay open. I'm not sure if this is a problem with the gun or if the previous owner set it up like this for some reason. How would I check to see?

Also I noticed a ton of duds, maybe 2-3 per 10 round clip. I was using Winchester range ammo. I don't know if the new gun is striking light or not. I looked at the back of the dud bullets and it looked like it was striking okay, although maybe not as hard as my older mark 3 target pistol. It does have a Tandemkross trigger, but it looks like the stock firing pin.

Any feedback on what to do would be very much appreciated! It's a very cool looking gun, but I do want it to work right. 

[MacGyver]

I’d start with a solid cleaning.

No penalty for total disassembly and proper lubrication of the entire thing. 

[Sleep profit]

I have a mark 4. I would advise to change ammo to CCI or Blazer lots of 22s are ammo sensitive  As far as the bolt mine locks backs after last round unless the mag is out make sure mag is seated and not loose  maybe try a factory mag see if that works 

[10-Ring]

The earlier versions of this gun were really bad for light strikes due to crud in the firing pin channel and/or the bolt face itself. They can have weak firing pin springs as well due to age. As others have said, a good cleaning is the first thing you want to do. 

[slickrick0999]

3 hours ago, MacGyver said:

I’d start with a solid cleaning.

No penalty for total disassembly and proper lubrication of the entire thing. 

Absolutely 

[Bartonand]

Dont send it to ruger!! They will remove all aftermarket parts and not return them

[BigK]

Most .22LR ammo, especially bulk target ammo, is notoriously dirty. Nonetheless, my Ruger Mark II is VERY forgiving and can go 5 or 6 trips to the range w/out needing to clean the firing pin channel. My Mark IV 22/45 LITE is considerably more finicky. I can barely get a 333 rd box of cheap target rounds through it w/out needing to clean it. Luckily it's really easy to disassemble.

My advice would be to order replacement springs from Ruger now, so you'll be ready in case a good cleaning doesn't fix the light strikes. I'd be really surprised if that doctored up gun doesn't have some springs that are too light. It's been my experience that lightened springs wear out way faster.

[Choatecav]

9 hours ago, BigK said:

Most .22LR ammo, especially bulk target ammo, is notoriously dirty. Nonetheless, my Ruger Mark II is VERY forgiving and can go 5 or 6 trips to the range w/out needing to clean the firing pin channel. My Mark IV 22/45 LITE is considerably more finicky. I can barely get a 333 rd box of cheap target rounds through it w/out needing to clean it. Luckily it's really easy to disassemble.

My advice would be to order replacement springs from Ruger now, so you'll be ready in case a good cleaning doesn't fix the light strikes. I'd be really surprised if that doctored up gun doesn't have some springs that are too light. It's been my experience that lightened springs wear out way faster.

I agree with BigK  on all of this.  Mine will eat almost anything and while I do clean it, on those occasions where I have run high volumes of dirty ammo through it, not a problem.  

[Danno919]

Thanks for the suggestions guys. I cleaned it really well, but the problems persist. I'll order a new spring kit from Ruger to see if that fixes things. Would a new spring kit help with the bolt not locking back on the last shot?