Home Forums Hunting & Shooting Gunsmithing Types of bedding and their intended purpose

I'm still in learning mode since finding this site. I thought I knew quite a bit about rifles, but I have come to the realization that just isn't true.

I'm hoping someone can tell me the various types/styles of bedding a bolt action rifle, their intended purpose and the pros/cons of each method.

Enlighten me please.

you can use any non/low shrinkage material that is durable and hard for bedding. the goal is straight forward, keep the relationship between the stock and the barreled action dead solid and repeatable. I have used metal based body filler when trying to see if a stock would fit a completely wrong action with good results for a short time.

I prefer devcon 10110 for it's compromise between strength and workability. it is more expensive, but that is because it is worth it.

1. Free floating method. Clearance from the stock forend to the front of the receiver/lug.

Tikka,Sako,Model 70,Kimber and some other brands come this way from the factory . There are some that are free floated 1 inch from the front of the action and they generally have a stock screw in the recoil lug.

2. Pressure tip method. Barrel is free floated except for a pressure point an inch or two from the foreend tip that dampens vibrations.

Weatherby and Remingtons come from the factory this way but there are exceptions in each line dependent on barrel and contour. I think most would argue that this method is a bandaid solution to make up for slop in the inletting. Weattherby rifles have their front action screw in the recoil lug and benefit from having the first one inch of barrel to be full contact bedded.

3. Full length bedding method . Zero clearance fit from the tang area of the action to the foreend of the stock.

Mostly performed by custom stock makers and gunsmiths on featherweight barrels. Standard technique used by NULA. On a wood stocked gun requires some time to do a stress free barrel installation.

4.Pillar bedding. Pillars made out of aluminum,steel,Carbon used on the guard screws to keep the stock from compressing when torquing the screws.

Some factory rifles come pillar bedded, Kimber montana is one off the top of my head and it is completely free floated as well.

All properly done will result in a accurate rifle, one of the biggest variables in this is the type of barrel contour being used, the method of rifling(cut vs button vs hammerforged), location of receiver stock screws and length of barrel.

A common ploy is to free float the barrel and test for accuracy. Then apply up pressure at the tip by inserting business cards or whatever between the forend and the barrel and shoot again. If it shoots more accurately add an epoxy pad in place of the cards (or whatever).

No predicting which method will work best with most barrels.

To me the purpose of bedding is twofold:

1) Couple the forces generated by recoil into the stock (and you) in a way that is precisely repeatable from shot to shot. The action and stock are as one.

2) Couple those forces evenly across the area of the interface.

People have success with any number of techniques. Keep the objectives in mind when choosing the one that appeals to you. It helps if you can visualize the action interfacing with the stock in recoil and follow the forces. Don't forget torque.

Free floating has always worked for me with the action bedded in acra glass or JB weld. The recoil lug must only touch at the back, no contact at sides, front or bottom.

Col Whelen came up with it about 60 years ago. He was right then and still is.

Yeah the coupling should be to frequencies an order of magnitude above those of the recoil reaction.
If it takes a millisecond for the bullet to accelerate and exit, then we want the coupling between receiver and stock good to 10 kHz. The way I test is to grab the rifle at the stock wrist with my right hand and punch the barrel with my left palm. This should made a ~ 1 kHz exponentially damped sinusoidal sound. Anything wrong with the bedding job will cause fast damping [lack of sustain] and/or harmonic distortion [buzzing] in the sound. If it does not sound right, chisel it out and start over... it is not worth testing at the range.

Of course many perform bedding as ritual and evaluate it based on looks.
But maybe some have a shake table and synchronized strobe light:)

I like Devcon Steel Putty. Bart Bobbitt is 10X better shot than me, and he likes Marine Tex.

Jeez, and I thought I'd over analyzed it.

Seriously, I'll have to think about that now. And barrel vibration dampening in general. Had the idea dampening was the secret behind bedding at the tip. Nodes and all that, which is maybe why it works with some barrels and not with others.

The purpose of bedding is to get a solid, repeatable connection between the action and the stock. When an action is machined and heat treated it tends to flex slightly and thus is not exactly the same as another action of the same make and model. Bedding allows the stock to be custom molded to the action.
For the amateur like me, Brownells and Midway have kits that have everything you need including instructions to bed a couple of rifles. I've done a couple and the results have been excellent. The only way I think you could really mess up is to not get enough release everywhere and glue one together.

Thanks Blacktailer, I've never done one, but I'm on the verge.

I'd really like to do it myself rather than paying to have it done. This thread has been very helpful as well as some of the videos I've been watching.

After using a bunch of bedding agents I tried used Probed 2000. The primary reason is work time, you have a looooooooong time to put it down make sure everything is in place . It mixes extremely well and the quantity does not have to be crazy exact. Bedding stays the same year after year and after going thru 10 kits or so I have never had a batch not setup properly. I would not use anything else. If all you have ever used is acraglas you need to try this stuff out, you will never use brownells overpriced epoxy ever again.

But then I like Acraglas Gel in the shop size containers for the same qualities. Long pot life, good consistency, mixes 50%resin/50%hardener, not so sensitive to proportion variations, easy to mix just a little if you want it for something else, long shelf life, easy to mix, can add powdered metals if you like.

IMHO it's best to pick a well regarded product and stick(!) with it. The Acraglas Gel got easier to use as I adjusted my technique to match its properties.

Everything you can do with Acra glass and acra glass gell you can do better with Probed everything. Have you used Probed?????

No. I'm satisfied with Acraglas Gel. Gives me good, predictable results, can't see where another product would do better.

Not knocking Pro-Bed, looks like a good product. But if you look at the technical data any quality epoxy will work for bedding in at least 95% of cases. (IMHO of course) I've worked with Acraglas Gel long enough that it holds no surprises.

Acraglas sucks. Devcon 10110 is better... Another thing about bedding is everyone has their own way of doing it. With that being said, the tell tell sign that you did it right will be perfectly clear on the target

I used Midways product once. It did not get hard enough to suit me. Have always used original Acraglas with good results. Need to try Pro-bed or 10110 sometime. Have often pondered just what acraglas is, you can bet that Brownells did not invent or manufacture it. They get it made or just repackage it.

My gunsmith friend uses Devcon and nothing else.

After researching, I came to the conclusion Devcon 10110 is what I was going to try first.

I'll look into the Probed 2000; as always, thanks Ed.

Have a cap full of wd40 and 10 qtips handy and you can keep the 10110 edges cleaned up very nicely and quickly, just do it when the mud is wet.