Bedding, Pillar bedding, magazine boxes, tangs and recoil lugs....

[sean69]

Read a lot of differing opinions methods and thoughts about bedding in general over the years and wondering what/when and where to use the differing bedding methods as well as when and how to decide if a barrel should be bedded or floated.

First off, floating the barrel - floating a heavy barrel seems pretty self explanatory, but is there any benefit in bedding a thin barrel or drawbacks to floating it?

Pillar bedding seems to be a method to actually float the action as well, but I see it commonly done with either full length or front and back action bedding. What is the actual benefit of pillars in these cases?

Front and back vs. full length action bedding. how is this decision made? Is it by action type i.e. something with a magazine well (Rem 700 etc) vs. a solid body action? Working on a custom stock for a Kimber 84M right now - the action to stock (really nice piece of claro walnut) fit is quite literally perfect, no high spots, no low spots 100% contact... wondering if front and back bedding is enough or if full length is still in order.

Magazine boxes, should not touch the action - seems pretty common to free float them. What is the common technique to keep them from rattling around in the magazine inlet?

Recoil lugs, I see almost exclusively that there should be space between the front and sides of the lug and stock. Why?

Rear tang. This one I see about 50/50 that there should be no space vs. 1/32-1/16 gap there. Is this also dependent on action type - where the rear portion of the tang is also part of the recoil system? (rear tang acts as a recoil lug)

 

[Yail Bloor]

Recoil lugs, I see almost exclusively that there should be space between the front and sides of the lug and stock. Why?

Ease of removal. The only part of the recoil lug that matters as pertains to bedding is the back surface as that is the direction of recoil energy. The front and the sides are irrelevant.

 

[Potashminer]

I can't help with all of these questions, but regarding the Recoil lug question - from Roy Dunlap and Jim Carmichael books, the front,sides and bottom of the recoil lugs should not touch - just the rear face - reason given both times was to allow future dis-assembly - a perfectly tightly fitted lug will not easily be withdrawn from the bedding, and will likely result in shavings at the bottom upon re-installation - defeating the purpose of that bedding.

Regarding the rear tang - from the Kuhnhausen Mauser Shop Manual - want that clearance so that the rear tang can not become a recoil lug on a Mauser 98. I would imagine any taper shaped tang that is inlet into the stock would work to spilt the stock, due to flex in the wood stock upon recoil.

The writer Nathan Forster has a couple books on accurizing, and has a discussion regarding front and back only versus full action bedding - I will have to re-read that for his specifics...

 

[Potashminer]

Okay, here is what Nathan Forster says - F&R means Front and Rear bedding; FL means Full Length:

"A full length bedding job is certainly very sound and can fully stabilize a wooden rifle stock, preventing the wood from warping between the tang and recoil lug which could potentially place stress on the action. FL bedding can also help eliminate stock flexing in plastic rifle stock designs. But in all honesty, I have never seen any major differences in accuracy between the two methods, as long as prep methods and bedding techniques are sound. Provided the stock is sound (sealed if wooden), there are no high spots in the mid action area when F&R bedding, and care is taken with bungee tension, the accuracy potential is generally the same with both methods. My advice is that if you are nervous about bedding, adopt F&R bedding unless you are bedding an M700 or Tikka. If you are an experienced workman, adopt FL bedding but be wary of some action and/or stock designs (such as the Ruger M77) which could get you into trouble. If bedding the Hogue stock, I recommend front and rear bedding. Most folk will also find F&R bedding an easier option when bedding Mauser rifles. The Ruger M77 needs to be F&R bedded due to the non-removable trigger unit. The Remington M700 and Tikka T3 are generally straight forwards to bed, whether utilizing F&R or FL bedding. But as suggested, if a Hogue stock is employed, F&R bedding is recommended due to the more difficult nature of the rubber molding."

Nathan Foster. The Practical Guide To Bolt Action Rifle Accurizing And Maintenance (Kindle Locations 1759-1769).

 

[sean69]

Ease of removal. The only part of the recoil lug that matters as pertains to bedding is the back surface as that is the direction of recoil energy. The front and the sides are irrelevant.

Makes sense..

the front,sides and bottom of the recoil lugs should not touch - just the rear face - reason given both times was to allow future dis-assembly - a perfectly tightly fitted lug will not easily be withdrawn from the bedding, and will likely result in shavings at the bottom upon re-installation - defeating the purpose of that bedding.

Ahh very interesting!

The writer Nathan Forster has a couple books on accurizing, and has a discussion regarding front and back only versus full action bedding - I will have to re-read that for his specifics...

I had not considered that there may be books written on the subject - I am really more interested in the math and physics to be truthful.

Interesting point :

A full length bedding job is certainly very sound and can fully stabilize a wooden rifle stock, preventing the wood from warping between the tang and recoil lug

It seems to me that with an action that has a large magazine well (Rem 700, Kimber) that the amount of bedding along the sides of the action across the magazine well (in a wooden stock) is not enough to prevent any sort of warpage or flexing. Especially considering that epoxies are somewhat elastic by nature.

 

[guntech]

Magazine boxes should have clearance between the action and bottom metal. When the action screws are tight you should be able to move the magazine box easily, if there is not enough clearance the action can be bent when the screws are tightened. It's not going to rattle around when you carry it...

 

[Potashminer]

.... I had not considered that there may be books written on the subject - I am really more interested in the math and physics to be truthful...

Might want to check out his website - I think he borders on fanatical for accuracy tricks and tuning - has developed and sells several specific epoxy formulas for bedding and filling - loses me in the chemistry discussions. Seems to be knowledgeable about the vibrations and flexing going on. https://www.ballisticstudies.com