In one sentence what is the purpose for bedding an action?

To mate the receiver/bottom metal (and in some cases a portion of the barrel) to the stock to provide a perfect form fit that is far less susceptible to shrinkage, expansion, contraction and compression than is the stock material alone.

fyj,

Do Brenchrest shooters glue their action in because action screws create stress?

Can a hunting rifle action be glued in?

Thank you.

quote:

Do Brenchrest shooters glue their action in because action screws create stress?

Can a hunting rifle action be glued in?

Yes and yes, but it would be overkill in anything other than a bench gun IMO. Like if you wanted to change triggers, work on the stock, etc.

Also, it appears to me the methods applied to bench guns have to be taken as a whole- many modifications adding up to the guns accuracy- what it amounts to is eliminating variables, bringing the actual target performance closer to what the shooter can do, rather then what the gun does. I don't believe under hunting conditions gluing an action would offer any advantage.

But it's your rifle

Here's the best quote I have read about bedding (written by Terry Cross):

quote:

I look at "bedding" simply as an adapter between the host stock and the barreled action that mates two imperfect surfaces allowing no change in that mating over temperature, recoil, transport and other extremes without inducing any addtional stress in either the stock or barreled action. Anything that moves between the two is a bad thing.

Pictures are worth 1000 words:






As for gluing in a hunting rifle, bad things can ahppen if gunk gets between teh barrel and the stock. Worse things can happen when water gets in there. The only way I would even consider gluing in a hunting rifle would be if it was FL -glued in bedded (and that sort of defeats the purpose of gluing one in).

Since bench guns are not subject to the dirt and abuse of hunting rifles, it is not an issue to have them glued in.

Ok. Seems obvious now.... don't glue the action in a hunting rifle.

Thanks.

Two words:

Relieve Stress.

Reloader

quote:

Originally posted by Buliwyf:
fyj,

Do Brenchrest shooters glue their action in because action screws create stress?

Can a hunting rifle action be glued in?

Thank you.

That takes more than one sentence to answer.

One key to accuracy and precision is “repeatability.†If the barreled action is sitting in a stock that 1) isn’t a perfect fit (inletting) and 2) is susceptible to compression, expansion, and contraction, you are going to have unequal and unpredictable pressure on the receiver depending upon what the stock material is doiing or not doing.

As tin can stated above, “gluing in†a barreled action isn’t real practical, or even necessary for most people.

As with most endeavors in life it is normally wise to determine exactly what you are trying to fix or accomplish before you decide on a plan of action.

quote:

In one sentence what is the purpose for bedding an action?

To create a situation where the relationship between the stock and the barreled action remains the same after each shot is fired.

Mike

well you see when you're walking down the street and see this really pretty girl and you're in need of some action bedding then comes to mind

quote:

Originally posted by butchloc:
well you see when you're walking down the street and see this really pretty girl and you're in need of some action bedding then comes to mind

For some guys, she don't really have to be pretty.....Billy Klintoun (the arab) come to mind?

Poor inletting.

Bedding is for accuracy.

Before the bullet exits, the barrelled action moves in reaction to recoil. This changes the point of impact.

If the recoil energy is tranfered in different directions and at different rates with each shot, the point of impact will change with each shot.

Bedding is for tranfering the recoil reaction in a consistant way.
Bedding if for transfering the recoil reaction in a low compliance path.


Because this would be a non issue in a very heavy barrelled action shooting a very light bullet and powder mass, I do not need to bed rifles that shoot 33 gr bullets and have barrelled actions that weigh 5 pounds.

Bedding gets the 5 pound barrelled action connected to the 2 pounds stock is a stiff and consistant way to make the 7 pound total act as a single mass in reaction.

For the rest of the mass in the reaction...

How tightly the rifle is held to the shoulder can affect the point of impact, as can the compliace and distributed mass of the recoil pad, clothing, flesh, shoulder, and body.

quote:

Originally posted by Buliwyf:
In one sentence what is the purpose for bedding an action?

To properly mate an action to a stock for which it was not purposefully made.

Reloader has answered your question perfectly...A properly done bedding job has to be stress free. There are many opinions on how to get it that way, but the main goal should be that when you tourque the action screws, the action itself shall not twist in any way. Obviosly you need a very strong bedding compound that has very little shrinkage to achieve this. As far as gluing in, it's not nessecary on a hunting rifle and some feel not even on a benchrest rifle.

quote:

Originally posted by Buliwyf:
In one sentence what is the purpose for bedding an action?

What kind of a question is this?? Bedding is intended to keep the barreled action and the stock from parting company when the rifle is fired......

(The better they fit together, the better the accuracy will be, and the less likelihood there is of the steel parts splitting the stock on recoil!)

Ok. Thank you for your comments.

My summary understanding is: The purpose of bedding is to create a stress free environment for the action and barrel. So, if done right, then standard bedding, pillar bedding, and glue-in can accomplish this. However, glue-in is not practical for a hunting rifle. I suppose wood, laminate, or composite stock material has some impact on whether to use pillars or standard bedding.

Happy Holidays,

B

quote:

Originally posted by Buliwyf:
Ok. Thank you for your comments.

My summary understanding is: The purpose of bedding is to create a stress free environment for the action and barrel. So, if done right, then standard bedding, pillar bedding, and glue-in can accomplish this. However, glue-in is not practical for a hunting rifle. I suppose wood, laminate, or composite stock material has some impact on whether to use pillars or standard bedding.

Happy Holidays,

B

Almost right; SDH said it but in too few words. Bedding is a less expensive way to achieve perfect stock-to-action fit.

It is a short cut (necessary for most of us with shallow pockets) to get what a master stockmaker can do with just the wood. A hunting rifle bedded with top-notch inletting won't shoot any better after it's glass bedded.

Pillars help with soft wood or cheap synthetic stock materials; probably don't do much for dense wood or synthetics with hard materials in the action screw areas.

Glue means you can't disassemble the gun in the field for maintenance (oops-I mean you can't re-assemble it in the field).

quote:

My summary understanding is: The purpose of bedding is to create a stress free environment for the action and barrel.

The bedding will not work without stress.

That stress free talk is about how the bedding is formed.

Once the bedding is hard, we want lots of stress to hold the barrelled action tight to the stock.

In a stress-strain curve, the stress is the force and the strain is the bending.

We tighten the screws and that causes a force of the action against the bedding and there is static stress in the bedding, action, and screws.

When the guns is fired, there is dynamic stress on the recoil lug and screws.

tigger,

What you said is only partially true. It is true that bedding is certainly cheaper than trying to hand working trying to fit an action to wood (or any other stock). Yet, it is the ONLY way to get an absolutely perfect fit of action to stock. When you bed an action properly w/ quality matieral (acra-glass, steel-bed, etc.), it is fit to tollerances of 10,000s. That is simply not humanly possible to obtain by hand working a stock.

To get back to the point. Bedding is everything, it reduces and/or eliminates the stress of recoil in wrong places and puts it consistently - shot after shot - where it should be. Inconsistent flex and vibrations are what destory accuracy. These are minimized and accuracy is the result.

Example: I just finished a friends factory 700 Rem. XCR (at lest I think that's what there calling them?) From the factory w/ its tupperware stock it was grouping quality factory ammo consistently on a 8.5x11 sheet of paper! He asked me to help. Aluminum pilliars and bedding the front lug (and floating the barrel)was ready to test this afternoon. 150 gr. factory - 3 shots - 1.1" at 100 yards.

Handloads will likely cut that by a 1/3, but he doesn't handload.

it is a means to create a repeatable surface, that is hard, adds in resistance to warping, seals the barrel channel, generally makes the rifle more consistent due to the metal repeating the same actions without much consideration to heat or humidity, and aids in protecting the stock from the cummulative effects of recoil.

whew!

what does that mean? you can take the gun out of the sotck, and it goes back to the same place, it shoots pretty consistently -generally better- than an unbedded rifle, and makes a "surface" area or material that is resistant to chipout.

heh, and covers up bad inletting

jeffe

quote:

Originally posted by jeffeosso:

heh, and covers up bad inletting

jeffe

Finally, something you are eminently qualified to speak on.

quote:

Originally posted by Poleax:

quote:

Originally posted by jeffeosso:

heh, and covers up bad inletting

jeffe

Finally, something you are eminently qualified to speak on.

quote:

Originally posted by Buliwyf:
In one sentence what is the purpose for bedding an action?

To create consistant "stability" for the mating of the stock and action.
---

If you are dealing with Termite Food, the more of it you remove and replace with the Synthetic, the more "stabile" it becomes. And if you remove the exact right amount of Termite Food, it them becomes - TaDaaa - a totally Synthetic Stock with consistant stability.

As a very knowledgeable experienced Hunter has often said, "Lifes to short to Hunt with constantly warping, but pretty Termite Food stocked firearms."

Good hunting and clean 1-shot kills.

Ok, let's talk a minute about stress and strain. When the actions screws are tightened are you creating stess? And is that stess measured by strain? What are the units of measurement for stress and strain?

I've thought in terms of stress when the action was in a bind with a high point in the mating surface area. I've thought the barrel was free floated except on substantial barrels where a small portion of the barrel was bedded to take stress/strain off the action threads.

Happy Holidays,

B

quote:

Almost right; SDH said it but in too few words. Bedding is a less expensive way to achieve perfect stock-to-action fit.

It is a short cut (necessary for most of us with shallow pockets) to get what a master stockmaker can do with just the wood. A hunting rifle bedded with top-notch inletting won't shoot any better after it's glass bedded.

I'm honestly shocked that in this day and age, anyone would dispute the qualities and advantages of glass bedding over the old method of blackening a stock and taking little by little off by hand until you reached the desired inletting depth and profile.

I've seen some fantastic inletting work that was done by hand, but it is a physical impossibility to acheive the contact on the receiver by using wood alone that will match what glass bedding will do.

While you may not increase the accuracy potential of a rifle with glass bedding over a finely inletted stock, you will certainly increase it's repeatability to perform it's accuracy year after year and shot after shot.

Even with the top-of-the-line inletting at work, the accuracy of a rifle will never truely be known without glass bedding.

There's only one guy that ever breathed a breath who had the potential to pull off an inletting job as good as glass bedding.....

He was a carpenter and his birthday is tomorrow.....

Merry Christmas to all and hope you all have a great New Year.

quote:

Originally posted by jeffeosso:
it is a means to .. seals the barrel channel,..

jeffe

My bedding may seal against brush but not moisture.

A dollar bill wrapped around the barrel must freely slide to within an inch of the receiver, when I'm done.

quote:

Originally posted by tnekkcc:

quote:

Originally posted by jeffeosso:
it is a means to .. seals the barrel channel,..

jeffe

My bedding may seal against brush but not moisture.

A dollar bill wrapped around the barrel must freely slide to within an inch of the receiver, when I'm done.

If you thin the bedding material and paint a thin layer down the barrel channel it will help seal the stock and repel moisture.You can do this and still free float the barrel.

On synthetic stocks I do the same on the relief cut for the bolt handle to seal that area also.

quote:

Originally posted by triggerguard1:

1. I'm honestly shocked that in this day and age, anyone would dispute the qualities and advantages of glass bedding over the old method of blackening a stock and taking little by little off by hand until you reached the desired inletting depth and profile.

2. While you may not increase the accuracy potential of a rifle with glass bedding over a finely inletted stock



3. you will certainly increase it's repeatability to perform it's accuracy year after year and shot after shot.

4. Even with the top-of-the-line inletting at work, the accuracy of a rifle will never truely be known without glass bedding.



Merry Christmas to all and hope you all have a great New Year.

Merry Christmas to you too but... I didn't dispute anything about the qualities of glass bedding and I was very specific about hunting rifles, not precision target rifles.

2. Here you agree with me

3. Not necessarily; I have many rifles 50 years to 100 years old that still shoot to point of aim and still shoot 1" groups with iron sights or scopes.

4. I think you are disagreeing with me here and yourself in sentence 2?

Anyway, its hard to say exactly what one means in a few posts and its Christmas and I'm out of flame juice. (We'll fix that shortly!) So I hope you and every other member/lurker/ex-member has a wonderful time tomorrow!

quote:

Originally posted by fyj:

quote:

Originally posted by tnekkcc:

quote:

Originally posted by jeffeosso:
it is a means to .. seals the barrel channel,..

jeffe

My bedding may seal against brush but not moisture.

A dollar bill wrapped around the barrel must freely slide to within an inch of the receiver, when I'm done.

If you thin the bedding material and paint a thin layer down the barrel channel it will help seal the stock and repel moisture.You can do this and still free float the barrel.

On synthetic stocks I do the same on the relief cut for the bolt handle to seal that area also.

I use Devcon Steel Putty, which is way to thick for that.

Which bedding material are you using and what are you thinning with?

triggerguard1

[QUOTE]There's only one guy that ever breathed a breath who had the potential to pull off an inletting job as good as glass bedding.....

He was a carpenter and his birthday is tomorrow.....QUOTE]
Matt, That was good!

quote:

Originally posted by tnekkcc:

quote:

Originally posted by fyj:

quote:

Originally posted by tnekkcc:

quote:

Originally posted by jeffeosso:
it is a means to .. seals the barrel channel,..

jeffe

My bedding may seal against brush but not moisture.

A dollar bill wrapped around the barrel must freely slide to within an inch of the receiver, when I'm done.

If you thin the bedding material and paint a thin layer down the barrel channel it will help seal the stock and repel moisture.You can do this and still free float the barrel.

On synthetic stocks I do the same on the relief cut for the bolt handle to seal that area also.

I use Devcon Steel Putty, which is way to thick for that.

Which bedding material are you using and what are you thinning with?

I also use Devcon titanium putty, but normally use the liquid thinned with Brownell’s Acra Glass thinner or similar generic solvent for painting in barrel channels. You can also thin the putty down with the same stuff if you need to. All you’re doing is brushing a thin layer on to seal the surface, and it doesn’t have to be thick enough to resist any compression since nothing is really touching it.

You could probably achieve the same results by using a poly spar varnish if you wanted to.

quote:

4. I think you are disagreeing with me here and yourself in sentence 2?

Read my wording carefuly below.

quote:

While you may not increasethe accuracy potential of a rifle with glass bedding over a finely inletted stock, you will certainly increase it's repeatability to perform it's accuracy year after year and shot after shot.

While you may not......the chances are extremely rare that you won't, even if you've done everything right.

Of course.....all of this gets down to what you expect your "hunting rifle" to do.

I expect 1/2MOA consistently out of all my rifles.....I acheive that by a variety of techniques, but all of them include glass bedding.
I've achieved these same results without bedding, but later had POI changes, as well as extreme spread changes when heading back the range the next time, but this is getting back to what I expect it to do and what it had already proved it could.