Shim in recoil lug slot

[Bidwell]

I have a Howa superlite 308, and the barrel has some pretty significant contact with the stock. I contacted howa and they said this shouldn't be happening. I saw some things online that actually said this was a feature not a bug, but howa disagrees. Anyway, what I found is the recoil lug is just about exactly. 025 inches shorter than the recoil lug slot in the stock. When torqueing the front action screw I can see the action sinking into the stock and the barrel making contract. I sacrificed a .025 feeler gauge and dremmeled it out so it fits pretty snug in the slit and drilled a hole for the action screw. I haven't fully torqued the action screws yet but I can tell it's helping a lot. The barrel is now free floating. I thought I was pretty much done but then I saw some forum posts that said a recoil lug should never be shimmed and there should be some space between the lug and the bottom of the lug well. Having a hard time understanding why that would hurt anything but better to double check. I do t see any other way to free float other than significantly sanding the stock. It's carbon fiber and would rather not do that. To be clear, the fron action bolt is drilled into the recoil lug. Not sure how this would be any different that pillar bedding. At least in terms of having some metal to metal contact.

 

[MTN Humper]

I once shimmed the lug of a Remington model 700 in 7mm STW to free float the barrel to see what effect it had on my groups. It shot horribly. I removed the shim and that rifle shoots under 3/4”groups at 100 yards if I do my part. The barrel contacts the stock in this particular case and shoots much better than free floated.

I’m with you not understanding why a lug shouldn’t be shimmed and should be left with space underneath it. Hopefully someone with more knowledge will be able to explain that.

Might not be much help but that was my experience.

 

[insanelupus]

I used brass shim stock under the lug of a Ruger 77/22 Hornet. The barrel contact created patterns, not groups. Likely the reason it was sold, as the trapper buddy I bought it from, when asked how it shoots, stated, "I've killed coyotes with it. " LOL

Using the brass shim free floated the barrel and got me 0.50" groups. What started as an experiment became the solution.
A text with pictures and a hearty thank you for selling me the rifle was sent, with an explanation of what my fix was. It was all I could do to get a "hello" out of him for a few years.

I've used that trick on a few other small calibers since. Not ideal, but it works. So far no known issues. Provided the back of the lug contacts the stock well, I've not been too concerned about it.

Admittedly, there are better and more proper fixes. But then, I've taken apart a rifle or two, and read the trick dozens of times growing up, about a well oiled business card placed been the barrel channel and chamber area of the barrel to free float as well.

Certainly better options for a more refined/proper fix are undoubtedly avaliable. But when I used to help consult at a local pawn shop on the "weird stuff" that came in, I saw all manner of solutions to resolve real and perceived problems with regards to a firearm.

Folks can get awfully creative, but not always to the benefit of the firearm or themselves!

 

[grfox92]

If you bedded the action, all that space under the recoil lug would be filled by the epoxy. I wouldn't use any shims. I would bed the action.

Sent from my SM-G990U using Tapatalk

 

[Tmac]

Generally, if it works and shoots consistently, it's not wrong. Try it and if it shoots well you have your answer. Then the question becomes do you leave it as is or bed it in place….

 

[MTN Humper]

Please keep us updated with what you try and what works.

 

[Bidwell]

I once shimmed the lug of a Remington model 700 in 7mm STW to free float the barrel to see what effect it had on my groups. It shot horribly. I removed the shim and that rifle shoots under 3/4”groups at 100 yards if I do my part. The barrel contacts the stock in this particular case and shoots much better than free floated.

I’m with you not understanding why a lug shouldn’t be shimmed and should be left with space underneath it. Hopefully someone with more knowledge will be able to explain that.

Might not be much help but that was my experience.

Thanks, does the rem 700 front action screw go through the recoil lug? Not sure if that makes a difference but just curious.

 

[Bidwell]

Generally, if it works and shoots consistently, it's not wrong. Try it and if it shoots well you have your answer. Then the question becomes do you leave it as is or bed it in place….

I can get behind that logic. Yeah I think bedding is the way to go eventually if this seems to help.

 

[MTN Humper]

It’s been long enough ago I don’t remember. When I get home I’ll look.

 

[Bidwell]

Please keep us updated with what you try and what works.

Will do! It's supposed to be raining all weekend but hopefully I can get out there and try it out.

 

[Bidwell]

If you bedded the action, all that space under the recoil lug would be filled by the epoxy. I wouldn't use any shims. I would bed the action.

Sent from my SM-G990U using Tapatalk

Thanks. Do you think it would be ok to test with the shim? And for the final version maybe use a combination of both? Just epoxy that shim in the lug slot if it helps?

 

[Caseknife]

Rem 700 front action screw does not go into the recoil lug, it goes into the action, the recoil lug is captured between the barrel and action. If you have the shim installed already, shoot it and see what works. May be a simple fix, may not be. I would think that it would not be a secure fix because it may create a slip type surface and not capture the action. Bedding the area just in front of the recoil cutout is the proper way to do it and much more secure.

 

[Bidwell]

Rem 700 front action screw does not go into the recoil lug, it goes into the action, the recoil lug is captured between the barrel and action. If you have the shim installed already, shoot it and see what works. May be a simple fix, may not be. I would think that it would not be a secure fix because it may create a slip type surface and not capture the action. Bedding the area just in front of the recoil cutout is the proper way to do it and much more secure.

Sounds good. I've never actually bedded anything before. Do you have any recommendations in terms of products to use? Was probably going to buy the Brownells acraglas kit. But open to suggestions.

 

[TaperPin]

The reason it’s a horrible idea to shim under the recoil lug is because it’s a tiny surface area compared to the huge flat bedding surface built into the receiver. The big flat spot is there on purpose. If you need to shim anything put it on the bedding flat, not the recoil lug.

 

[Bidwell]

The reason it’s a horrible idea to shim under the recoil lug is because it’s a tiny surface area compared to the huge flat bedding surface built into the receiver. The big flat spot is there on purpose. If you need to shim anything put it on the bedding flat, not the recoil lug.

View attachment 832084

Thanks! This is a great point. I just tried adding my shim in the area you noted and this works well. My next question would it be better to also keep a shim under the lug so the space is filled or would that not matter? Also, would aluminum work as a shim material or is steel needed?

 

[TaperPin]

Thanks! This is a great point. I just tried adding my shim in the area you noted and this works well. My next question would it be better to also keep a shim under the lug so the space is filled or would that not matter? Also, would aluminum work as a shim material or is steel needed?

Even cardboard makes a good temporary shim. Old credit cards, plastic buckets, 2 liter soda bottles, etc. make good shims, as would any of the metals.

The problem with anything under the recoil lug, is it’s too hard to judge if it has too much pressure on it, and the redundancy doesn’t do anything the regular bedding surface can’t do by itself.

Even when glass bedded, the space under recoil lugs is usually relieved.

 

[Bidwell]

Even cardboard makes a good temporary shim. Old credit cards, plastic buckets, 2 liter soda bottles, etc. make good shims, as would any of the metals.

The problem with anything under the recoil lug, is it’s too hard to judge if it has too much pressure on it, and the redundancy doesn’t do anything the regular bedding surface can’t do by itself.

Even when glass bedded, the space under recoil lugs is usually relieved.

That makes sense. Thanks for the advice!

 

[TaperPin]

That makes sense. Thanks for the advice!

Glad to help.
That’s a really cool receiver design - should be a great gun.

 

[Bidwell]

Glad to help.
That’s a really cool receiver design - should be a great gun.

Thanks, it is an interesting design and I think it's going to be a great gun too once I get the kinks worked out. Fits me better than my other rifles.

 

[Castle Rock]

The reason it’s a horrible idea to shim under the recoil lug is because it’s a tiny surface area compared to the huge flat bedding surface built into the receiver. The big flat spot is there on purpose. If you need to shim anything put it on the bedding flat, not the recoil lug.

View attachment 832084

That would be true in most cases however the bolt being in the recoil lug means that the action will deflect under torque unless the bottom of the lug is supported as well

The correct thing to do here is wrap the barrel with tape to establish the correct clearance and bed the front of the action including under the lug