Split Groups

[PLhunter]

Biggest change is a new stock. But the severity of the split changes with seating depth. All groups are worse since the swap but not all are split like this. It’s like when it tightens up it splits into two tight groups. Any ideas?

 

[Ddubs20]

I had a similar issue after putting my rem 700 in a stockys. It drove me nuts for a year. I finally took it to a gunsmith and he found the pillars were loose in the stock. You couldn't tell by looking at it. Only once he drilled them out could you see how bad it was. He installed new pillars, rebedded, and it shoots great. He was convinced it was a bedding issue, I didn't think that was possible until he repaired the stock.

 

[PLhunter]

I had a similar issue after putting my rem 700 in a stockys. It drove me nuts for a year. I finally took it to a gunsmith and he found the pillars were loose in the stock. You couldn't tell by looking at it. Only once he drilled them out could you see how bad it was. He installed new pillars, rebedded, and it shoots great. He was convinced it was a bedding issue, I didn't think that was possible until he repaired the stock.

Okay, mine is a stocky’s Rokstok. It’s a tikka. I’ve been fighting it for a bit as well. It almost shoots okay but it’s shooting worse than with the factory and I’m more steady and comfortable behind the gun. So I think it’s a bedding issue but can’t figure it out.

 

[Tanner]

That is a bedding issue without a doubt especially if your same loads shot better in the factory Tupperware.

How tightly is the lug captured in the stock? If it’s loose it would be worth bedding, and maybe also dab bedding the lug and tang areas.

 

[PLhunter]

That is a bedding issue without a doubt especially if your same loads shot better in the factory Tupperware.

How tightly is the lug captured in the stock? If it’s loose it would be worth bedding, and maybe also dab bedding the lug and tang areas.

Lug is in there so damn tight that when I tried to remove it with heat and vice grips all I did was chip it. That puppy isn’t going anywhere. It’s a touch proud at .094-.096. UM said it was normal. I can’t find anything that says above .093 is okay. I’m thinking of taping the top of the lug for separation and then bedding. Thoughts?

 

[Harvey_NW]

Lug is in there so damn tight that when I tried to remove it with heat and vice grips all I did was chip it. That puppy isn’t going anywhere. It’s a touch proud at .094-.096. UM said it was normal. I can’t find anything that says above .093 is okay. I’m thinking of taping the top of the lug for separation and then bedding. Thoughts?

Try to measure with calipers the best you can and confirm if it's too proud, if so I probably wouldn't try the tape and bed idea. I've dealt with that before where the lug was a bit too big, and the action flexed with just enough torque on the screws to hold everything together for skim bedding. It audibly cracked when I loosened the screws after the bedding cured, and the only solution was to remove about .018" of material from the lug.

If the measurements don't appear to be obviously interfering, try reassembling by assuring the lug is in the action slot, tighten the action screws moderately snug, and drop it on the butt on the floor to seat it against the lug, then torque to 50+in/lb.

 

[PLhunter]

This values of .094-.096 are with calipers. Hard to ensure being perfectly level on such a small surface. Thus the range. The lug is 100% going in the action slot I have confirmed that with playdough . I’d remove material from the lug if I could get the damn thing out.

 

[PLhunter]

Try to measure with calipers the best you can and confirm if it's too proud, if so I probably wouldn't try the tape and bed idea. I've dealt with that before where the lug was a bit too big, and the action flexed with just enough torque on the screws to hold everything together for skim bedding. It audibly cracked when I loosened the screws after the bedding cured, and the only solution was to remove about .018" of material from the lug.

If the measurements don't appear to be obviously interfering, try reassembling by assuring the lug is in the action slot, tighten the action screws moderately snug, and drop it on the butt on the floor to seat it against the lug, then torque to 50+in/lb.

Also thanks for responding I was damn close to just taping and bedding.

 

[Harvey_NW]

This values of .094-.096 are with calipers. Hard to ensure being perfectly level on such a small surface. Thus the range. The lug is 100% going in the action slot I have confirmed that with playdough . I’d remove material from the lug if I could get the damn thing out.

What is the depth of the slot on your action? That one can be taken pretty accurately with calipers.

 

[83cj-7]

Make sure your bolt handle does not contact the stock at all. You can’t believe how many times bolt handle contact causes accuracy issues.

 

[doverpack12]

Following along. I have a tikka Rokstok that doesn’t shoot as well as factory either. I know my lug was high as well even after buying the UM to replace the MT mine came with. I’ve been adding LOP and improving slightly but not all the way there yet.

I’ve also retorqued action screws after shooting sessions and gotten a little more out of them at the same torque value and they were paint penned in to start with threads and witness mark. That might have seated my lug enough because it was very very tight to install. I pounded on it until I was worried about the stock and that measurement was still high.

Contemplating sending the stock back so they can make it right and also install the LOP kit they forgot to and wouldn’t send to me to install. Wood spacers and longer screws have worked so far.

 

[PLhunter]

Following along. I have a tikka Rokstok that doesn’t shoot as well as factory either. I know my lug was high as well even after buying the UM to replace the MT mine came with. I’ve been adding LOP and improving slightly but not all the way there yet.

I’ve also retorqued action screws after shooting sessions and gotten a little more out of them at the same torque value and they were paint penned in to start with threads and witness mark. That might have seated my lug enough because it was very very tight to install. I pounded on it until I was worried about the stock and that measurement was still high.

Mine is unmovable in any direction. Won’t come out. Won’t go in deeper. I could send it back. Might have to but I already dremeled some pressure spots not sure how they’d look on that.

I was considering the raising it and bedding until someone here said it cracked. My other option would be to try and file it in place.

 

[PLhunter]

Following along. I have a tikka Rokstok that doesn’t shoot as well as factory either. I know my lug was high as well even after buying the UM to replace the MT mine came with. I’ve been adding LOP and improving slightly but not all the way there yet.

I’ve also retorqued action screws after shooting sessions and gotten a little more out of them at the same torque value and they were paint penned in to start with threads and witness mark. That might have seated my lug enough because it was very very tight to install. I pounded on it until I was worried about the stock and that measurement was still high.

Contemplating sending the stock back so they can make it right and also install the LOP kit they forgot to and wouldn’t send to me to install. Wood spacers and longer screws have worked so far.

It’s disappointing and feels odd isn’t it. To feel so steady and comfortable behind the gun and to have groups actually get worse.

 

[Formidilosus]

Mine is unmovable in any direction. Won’t come out. Won’t go in deeper. I could send it back. Might have to but I already dremeled some pressure spots not sure how they’d look on that.

I was considering the raising it and bedding until someone here said it cracked. My other option would be to try and file it in place.

Send the stock back to have it looked at. Let me know when you do.

 

[PLhunter]

What is the depth of the slot on your action? That one can be taken pretty accurately with calipers.

Measures to .093 on the dot lug is .095. That might be just enough interference to cause some issues. Sending it back as @Formidilosus recommended.

 

[TaperPin]

Biggest change is a new stock. But the severity of the split changes with seating depth. All groups are worse since the swap but not all are split like this. It’s like when it tightens up it splits into two tight groups. Any ideas?

It’s probably a bedding issue, but if messing with the bedding doesn’t help, be aware some scope failures show quite small changes to groups. I had a loose internal lens that caused groups to look just like that.

An old school trick to test bedding is to cut two shims out of cereal box cardboard about an inch wide and long enough to wrap completely under the receiver with tails sticking out both sides. Put them right where the action screws are and tighten normally. The extra thickness snugs up the fit between receiver and stock, and also raises the receiver slightly so any binding of receiver on a high spot is relieved. Don’t force a nice tight bedding job and split the stock, but most factory stocks have a lot of slop in the fit. If the problem goes away it’s bedding, if not, you might have a weak firing pin or scope.

 

[PLhunter]

It’s probably a bedding issue, but if messing with the bedding doesn’t help, be aware some scope failures show quite small changes to groups. I had a loose internal lens that caused groups to look just like that.

An old school trick to test bedding is to cut two shims out of cereal box cardboard about an inch wide and long enough to wrap completely under the receiver with tails sticking out both sides. Put them right where the action screws are and tighten normally. The extra thickness snugs up the fit between receiver and stock, and also raises the receiver slightly so any binding of receiver on a high spot is relieved. Don’t force a nice tight bedding job and split the stock, but most factory stocks have a lot of slop in the fit. If the problem goes away it’s bedding, if not, you might have a weak firing pin or scope.

To add to the confounding factors I did switch scopes as well. I’d think a trijicon would be more reliable than the ultralight leupold it replaced but outliers happen.

 

[PLhunter]

Send the stock back to have it looked at. Let me know when you do.

It’s on its way.

 

[Steve300xcw]

Was given a ruger to fix as it wouldnt shoot. It was shooting 3 groups. You could just about call where the next round was going to land. Shot pretty good after I tightened up every bolt on the damn gun

 

[Formidilosus]

It’s on its way.

Send a PM and let me know what your name is, I will go by and check it.