Pillar bedding pros & cons

[THOMAST]

Hi all,
A friend is in the process of manufacturing a fibreglass reinforced stock for me. He has made several of these stocks before, using a blank to make the outer shell and then casting the action directly into it, using a suitable release agent.I'm not going to go into all the technical details here, suffice to say that he has a lot of happy customers who are using this "custom stock"
I want to add pillar bedding to this stock, but have heard some comments about pillars never mating up perfectly with the underside of the action, thus negating the whole accurate casting/bedding tecnique.
Any comments about the pro's and cons of pillar bedding please?

 

[Bart B]

Conventional epoxy bedding tends to apply pressure to a larger area around the receiver than just part of the tops of bedded pillars do.

The most accurate rifles I know of are conventionally bedded. I'm not referring to those that have once or twice in their barrel's lifetime shot 5 or 10 shots into some record-breaking group. Instead, it's those rifles that shoot a string of 20 or more consecutive shots into very small groups.

There's one exception; round receivers barreled for cartridges shooting fast bullets heavier than about 160 grains. There's enough torque on the receiver as the bullet accelerates down the barrel to often work the receiver a bit loose from its epoxy bedding. Sometimes pillar bedding helps keep the receiver in place. But I'd rather glue that round receiver in a square-bottom sleeve, then conventionally bed it.

 

[uncleB]

THOMAST,
If a pillar bedding job is done correctly by someone who really knows what they are doing there is only pros and no cons.
UB

 

[Fiftydriver]

I would agree with UncleB on his comments. If done properly a pillar bedding system offers the best of both worlds, total stress free bedding with a non compressible, uneffected by environmental changes bedding system. That can not be said for a skim bedded or glued in bedding system only, especially in a wood stock.

Kirby Allen(50)

 

[7RHB]

Thomast, I'm with Uncle B and kirby on this one . No down side if they're installed correctly. ---7mmrhb

 

[goodgrouper]

ANother vote with 7rhb, uncle b, and fifty driver.

Back in the day, not much was known about how to properly pillar and glass an action, especially in the new (then) composite stocks coming out. But now, it has been proven time and time again in tens of thousands of high dollar rifles that it it THE way to go if done by someone who knows what they are doing. The fact that someone would try and steer you away from a good pillar job boggles the mind!

 

[EddieHarren]

You can take what Kirby, and the others say, to the bank. Every top competitor, that I know and build rifles for, are using pillars on their "bolt in" rifles.

 

[Bart B]

[ QUOTE ]
Every top competitor, that I know and build rifles for, are using pillars on their "bolt in" rifles.

[/ QUOTE ]It's obvious that we know different "top" competitors. Knowledgable rifle shooters know there's several major disciplines. But some aren't able to focus on more than one. That's fine with me. And obviously it's fine with everyone else, too.

 

[EddieHarren]

Well, enlighten me. What diciplines and which "top competitors" do not use pillar bedded rifles for their "bolt in", bolt guns.

 

[Bart B]

[ QUOTE ]
Well, enlighten me. What diciplines and which "top competitors" do not use pillar bedded rifles for their "bolt in", bolt guns.

[/ QUOTE ]What? Me enlighten you by telling you what discipline they're in and who builds their rifles with conventional bedding and all that other stuff, too? Then await your favorite pastime of ridiculing and making a mockery of me? You've done that before when I've mentioned these people and their disciplines. Now you're on your own. Go out yourself then learn something about the other shooting disciplines, find out just how accurate their long range rifles are as well as who builds them using conventional bedding. And they shoot just as accurate if not moreso than what your limited knowledge permits memory of. Not to mention that some are women; world champions as well as national ones setting and still holding records. Just think, you'll learn all this good stuff direct from them and won't have to put up with me telling you 'cause you won't believe me anyway.

 

[THOMAST]

[ QUOTE ]
THE way to go if done by someone who knows what they are doing.

[/ QUOTE ]
This seems to be the crux of the matter: how is it done properly? Is the pillar cut to a radius to match the bearing surface of the action(a Remington700)? Will this alone give you the tolerances required? Or is a bedding compound still needed over the pillar, once installed? If this is the case, why radius the pillar in the first place?
I'm after specifics please. I'm still undecided on which way to go - is reinforced glass fibre and resin strong enough to do the job, considering that it is a 7mm08 shooting 140gr bullets?
Please remember that I'm in South Africa and I have to make these components myself.. sheez! wish there was a Brownells or Midway local /ubbthreads/images/graemlins/frown.gif

 

[Bart B]

[ QUOTE ]
[ QUOTE ]
THE way to go if done by someone who knows what they are doing.

[/ QUOTE ]
This seems to be the crux of the matter: how is it done properly? Is the pillar cut to a radius to match the bearing surface of the action(a Remington700)? Will this alone give you the tolerances required? Or is a bedding compound still needed over the pillar, once installed? If this is the case, why radius the pillar in the first place?
I'm after specifics please. I'm still undecided on which way to go - is reinforced glass fibre and resin strong enough to do the job, considering that it is a 7mm08 shooting 140gr bullets?
Please remember that I'm in South Africa and I have to make these components myself.. sheez! wish there was a Brownells or Midway local /ubbthreads/images/graemlins/frown.gif

[/ QUOTE ]Most folks radius the pillar top to match the receiver's round bottom as well as fit them (if needed) to the trigger guard and floorplate hinge base. A few have put a thin coat of epoxy (Devcon Plastic Steel, Marine Tex, others a decent local 'smith may identify for you) on top of the pillar to get a more uniform contact. The fiber glass you mentioned may or may not work; I don't know exactly what it is. One guy said he used a spot tracing milling machine to make the top of the pillars a perfect fit to the bottoms of his Rem. 700 receiver. My guess is as long as there's fairly even contact at most places atop the piller, that should work fine.

I've conventionally epoxy bedded several McMillan and Winchester synthetic stocks. Their receiver area is as hard as decent wood and the bedding holds fine for belted magnum 30 caliber cartridges chambered in medium to heavy barrels. So either way with your 7-08 should do fine.

South Africa...neat place and nice folks, too. Absolutely great food in restaurants. Been to the big rifle range just west of Bloemfontein a couple of times shooting the SA Fullbore Nationals as part of the USA International Team. A man, Musgrave, makes great single shot actions down there but he may have retired. Contact the SA NRA and find out if he's still around and he may be able to help you out.

 

[THOMAST]

BartB, I've been to the military range at Bloemfontein- called "De Brugge". I partake in hunting rifle competitions which are set up in the hills at the range (and elsewhere).The shoot tries to emulate hunting conditions so you sometime shoot from uncomfortable positions. Plenty of shooting at gradients, over dead ground on 6 ranges , 3 at full size animal targets and 3 at 8" armour steel plates, set up at unknown distances up to 383 yards (350 meters)in a timespan that varies from 45 seconds to 2 minutes for 5 shots. No rangefinders allowed, so it can be a bit of an eye opener!
Musgrave factory closed its doors a while back.
If/when I decide to install pillars, I will go the Devcon route

 

[Fiftydriver]

Thomast,

TO pillar bedd a rifle properly there are certain steps you need to take to get it right. It is not like bedding or gluing in a barreled action and your good to go. A few more steps.

The pillars can be either radiused to match the receiver or they can be flat to contact on the centerline of a round receiver. As long as the contact is even this really makes little real difference in the finished product.

First thing you need to do is modify the stock to accept the pillars. The pillars should then be attached to the receiver using the receiver screws, just as the barreled receiver will be held in the stock when its finished.

A support pad should be built up around the barrel near the end of the forend to maintain proper center of the barrel in the barrel channel and also to provide proper freefloat after the job is over.

With the pillars attached to the barreled receiver, and laying on the work bench with the pillars pointing up, the stock should be set down on the receiver. It should drop on easily with no resistance. This will insure the pillars are not stressed as they set up.

If there are contacted then the stock needs to be relieved to correct this.

Once this is done, you use a small amount of 5 minute epoxy to "spot weld" the pillars to the stock. Put a bit around the top of each pillar and a bit in the holes in the stock. Put the stock on the barreled receiver, still on its back and then I generally apply several wraps of tape around the receiver and stock to hold it securely in place while the 5 minute epoxy sets up. I usually give this 30 minutes to an hour just to make sure the epoxy is securely holding the pillars so there is no shift in their position.

After this time I pull the receiver screws, put the rifle in a rifle cradle and pull out the barreled action. What you have are two pillars spot glued into the stock. I generally let these sit for most of a day to insure the epoxy fully cures so that when I tighten the receiver screws down on the pillars they pillars have a strong bond to prevent them from rotating.

After then are fully cured, then you bring in the conventional bedding compound, I generally use marine tex in most cases. Basically you give the rifle a conventional bedding job on top of the pillar job. The only difference really is that the stock has been relieved around the pillars so that you can get a good amount of bedding compound around the pillars for a secure bond.

When finished, you can instantly see if you have a properly bedded rifle as soon as you pull the barreled receiver out of the stock.

If you have radiused pillars, you should see the full clean surface of the pillar with bedding around it. There should be no spots where the bedding has gotten between the pillar and the receiver.

If your using a flat topped pillar, you should see bare metal just in front and in back of each receiver hole. These bare metal marks should be even on both sides in length and width. If they are not, the pillar is not straight in the bedding to the receiver.

The point of the pillars is to provide a consistant platform to apply a certain level of torque to the receiver screws which will not compress and will maintain this level of torque over a long period of time. Something a conventional glued in stock will not do, at least not with a bolt action rifle.

The conventional bedding around the pillars, controls the total surrounding surface of the receiver to control any rifle torquing and to prevent the receiver from shifting laterally or rotating at all under recoil.

The receiver screws should be totally floated in the center of the pillars so they will do nothing but hold the receiver down into the bedding. This also allows the recoil lug to do all the work as far as transmitting recoil energy from the barreled receiver to the stock which is how it should be.

Besides using a barrel bedding block or Barrel V-Block, pillar bedding the receiver is the most consistant and strongest bedding system you can have in your rifle.

Just one opinion so take it for what you will, alot of cats out there to skin!!!

Kirby Allen(50)