Glass bedding plunge... a few questions (before I learn things the hard way)

[clockwork_7mm_gator]

Gents,

I'm gradually gathering the nerve to try my hand at glass bedding. I've watched myriad video tutorials, I've read through several others, and that might be the problem: there are variances in the little things between them and other little things that seem to get glossed over quickly. So a few questions that I'm sure many of you can answer at the drop of a hat:

1. Will stock maker screws designed for m98 actions generally work with m98 clones or are they specifically meant for milsurp?

2. I've seen tutorials that avoid getting epoxy paste in the screw holes (on the stock, not the metal action itself -- all that filled with clay) and ones that put epoxy in intentionally and then run the actual screws in coated with release agent to get an extra snug hold (but then drill out the tang screw hole after). What is best practice here? And after bedding is done, if the tang rests against the stock, is it really necessary to sand a tiny gap between them to keep pressure off that spot?

3. When I think I'm all good on the recoil lug situation, I talk myself into more questions. I'm assuming you tape the front and bottom of the lug before putting in the epoxy to create a small gap between those sides of the lug and the hardened surface after bedding... but I don't understand why you wouldn't want the lug resting on the epoxy on front and back? (I get why you don't want it resting on wood pre-bedding.) Is there a major difference in how pressure/stress from recoil is distributing if the lug is technically only coming into contact with the bedding on the back?

Thanks for any/all help!

M

 

[Wyatt Smith]

I have glass bedded one rifle. My advice is to take your time. And to wax EVERYTHING you don’t want epoxy on.

 

[clockwork_7mm_gator]

Thanks, Wyatt. Part of what concerns me is how the action/trigger mechanisms come together around the inletting. It's a Zastava with double set triggers (with parts top and bottom), and the front action screw goes through the recoil lug. The action is closed off from the front action screw port, so it can't push epoxy up into the action, but I'm not sure how to keep epoxy out of those threads? Do I even try, or just put in release agent and let the screw push it out as it tightens?

I.e., I'm trying to plan clamping it on the wet epoxy without getting epoxy in places where it doesn't belong...

Fur

 

[IdaRam]

Hi c_7_g
I’m assuming this is a wood stock as opposed to synthetic? And what cartridge is this rifle chambered for? Heavy recoil makes it even more critical on certain aspects, although proper bedding on even light cartridges is obviously important.
Regarding Tang, it is critical that you have a small gap behind the tang. If the end of the tang contacts the stock, under recoil it will inevitably crack the wood behind the tang in the pistol grip.
As far as clearance underneath the tang, it all depends... very firearm specific. In some cases a small amount of clearance under the tang may be preferable. In others, not so much.
Regarding action screws, I always want clearance between the screws and the bedding. All kinds of issues may arise if the screws are tight in the hole. You can add clearance after bedding has cured if you choose.
Once again, depending on rifle and your preferred methodology, you can do the job in several steps. It doesn’t necessarily all have to be done at once.
Regarding clearance on the recoil lug. I won’t go into detail, just too long winded. You want clearance below and in front of the lug and in most cases each side. “Clearance” is a subjective term and may mean just a few thousandths of an inch, or 50 thousandths.
Obviously these are just my opinion, but based upon personal experience. Everyone has their opinions and preferred methods. There are many ways to skin the cat
Have fun with it. Everything can be fixed if you screw it up. Just make sure you have plenty of release agent everywhere. You wouldn’t be the first to get things glued together and not in a good way! And keep asking questions. You’ll get ‘er done

 

[Mr. Zorg]

I'd only caution what your envelope of "M98style rifles" includes. Zastava manufactured bolt actions specifically for the 8X57mm JS cartridge and not much longer. A military example would be the M48 which shares the action with the civilian Zastava M98, while the civilian Zastava LK M70 is best considered having interchangeable parts with M98 rifles that are not Zastava M98 rifles and their military equivalents.

It further muddies waters that M98 actions from outside Yugoslavia were also used in civilian and military rifles fabricated in Yugoslavia both by Zastava and local gunsmiths.

Measure twice, including requesting measurements of potential parts purchases, purchase once most likely is my advice, FWIW.

 

[clockwork_7mm_gator]

Thanks, Ram. Your recoil lug advice meshes with everything else I've seen. I'

lk m70 action

• clockwork_7mm_gator
• May 20, 2020

For bedding

m just not sure how the bottom have clearance will work when the action screw port is literally an extension of the lug. So I can tape the lug bottom on either side of the port, but inevitably, export will end up in the inserting around the port. (The top and bottom metal come together almost like a self-contained pillar.) So it seems like a good fit around that pillar would be good, but because it meets in the middle, I'm not sure how to achieve that while keeping epoxy out of the inside. The attached photo isn't great but shows what I mean, re: the lug fits into its in letting and then the screw port continues through the stock to meet the bottom half of the "pillar."

 

[clockwork_7mm_gator]

And now looking at photo, it's literally from the worst angle to show the lug.

Also, it's a 7x64.

 

[clockwork_7mm_gator]

These should help illustrate better.

 

[Wyatt Smith]

I think @sestoppelman has bedded a few zastava rifles. You might ask him.

 

[sestoppelman]

I have bedded all manner of BA rifles, its about the same process for all of them. Even the Ruger 77 with the dreaded angled lug is no big deal, treat it same as others.
I know that most info says to keep clearance around the front and sides of the lug. I don't bother with that. I think the more important part is the bottom. So I either just bed it and then scrape some away on the bottom or place a little tape over it. Most important is a good solid landing on the pad behind the lug. Best way to get that is scrape away a fair amount of wood with a gouge, but leave the height of the pad intact in places, allowing the bedding to fill the areas relieved.
There are many ways to accomplish all this, just know that the rougher the better for the bedding to grab hold of. I don't use any action screws, preferring to use large spring clamps to hold it all together while the bedding cures. I put clay or wads of tape or whatever is handy into screw holes to keep bedding out. I used to have a spray on product from Brownells that I used for release agent, but cant find it anymore so I use the blue stuff that comes with the Acra Glas kit, at least two good coats, or 3.
Otherwise advice above sounds in line with my methods, if you want to call them that. Be sure and mask off any areas on the top of the stock to keep overflow off your wood, if it matters.

Did you happen to notice if the web area just ahead of the trigger is cracked or not? They usually are. On the one I had like yours the wood piece was totally gone, so I drilled thru that area and glued a dowel thru it to stabilize it.

If after you bed it and it doesn't want to come apart, don't beat it all up. Throw it in a chest freezer and let it get really cold, this contracts the metal and assist in getting it apart.

After you have done a couple it becomes second nature. Good luck.

 

[fourfive8]

^^ Exactly, I like to bed in the dead of winter. If the bbld action is stubborn just leave it outside for a few hours to contract.

There are a ton of little tricks that are hard to specify in a tutorial or video. Mistakes are part of any education... but to prevent a potentially destructive experience, use plenty of release agent as Wyatt Smith posted- most any kind of paste wax works well. I use Q tips to apply it in tight areas and corners and holes. Some types of bedding compounds are easier to work with than others. I have tried several and either regular, original JB Weld works well if you're not bothered by slightly mis-matching colors- and it is actually matches pretty well with gray or black synthetic stocks.. The dedicated kit I like is Miles Gilbert.

Pillar bedding in conjunction with regular bedding is the bee's knees for consistent rifle performance but it is a level trickier than regular bedding without the pillars.

Yes, don't worry about getting the compound into the stock holes- drill them out later. Just make sure your action screws are well coated with release. Control and remove excess ooze-out with shaped and sharpened Popsicle sticks and acetone or alcohol and paper towels.

For wood stocks, you can relieve the split-out problem area around and behind the tang with a 1/16- 1/8" gap and bed that during the process. If you have bedded the recoil lug (s) properly there should be no problem with tang split-out after a correctly done job. The rear surface of the lug (s) should be contact bedded... but not the bottom, sides or front. Put a layer of masking tape on the bottom, sides and front and coat with release when bedding. Go for it and good luck!

 

[clockwork_7mm_gator]

I have bedded all manner of BA rifles, its about the same process for all of them. Even the Ruger 77 with the dreaded angled lug is no big deal, treat it same as others.
I know that most info says to keep clearance around the front and sides of the lug. I don't bother with that. I think the more important part is the bottom. So I either just bed it and then scrape some away on the bottom or place a little tape over it. Most important is a good solid landing on the pad behind the lug. Best way to get that is scrape away a fair amount of wood with a gouge, but leave the height of the pad intact in places, allowing the bedding to fill the areas relieved.
There are many ways to accomplish all this, just know that the rougher the better for the bedding to grab hold of. I don't use any action screws, preferring to use large spring clamps to hold it all together while the bedding cures. I put clay or wads of tape or whatever is handy into screw holes to keep bedding out. I used to have a spray on product from Brownells that I used for release agent, but cant find it anymore so I use the blue stuff that comes with the Acra Glas kit, at least two good coats, or 3.
Otherwise advice above sounds in line with my methods, if you want to call them that. Be sure and mask off any areas on the top of the stock to keep overflow off your wood, if it matters.

Did you happen to notice if the web area just ahead of the trigger is cracked or not? They usually are. On the one I had like yours the wood piece was totally gone, so I drilled thru that area and glued a dowel thru it to stabilize it.

If after you bed it and it doesn't want to come apart, don't beat it all up. Throw it in a chest freezer and let it get really cold, this contracts the metal and assist in getting it apart.

After you have done a couple it becomes second nature. Good luck.

I'd thought about claying up the front action screw ports and using a clamp to bypass the issue of epoxy inside the port. But also worried about not putting level/balanced pressure on the setup and somehow bedding it unevenly. (If that makes sense.)

When you did the m70 with double set did you remove the safety/triggers before bedding?

Thanks!

 

[clockwork_7mm_gator]

^^ Exactly, I like to bed in the dead of winter. If the bbld action is stubborn just leave it outside for a few hours to contract.

There are a ton of little tricks that are hard to specify in a tutorial or video. Mistakes are part of any education... but to prevent a potentially destructive experience, use plenty of release agent as Wyatt Smith posted- most any kind of paste wax works well. I use Q tips to apply it in tight areas and corners and holes. Some types of bedding compounds are easier to work with than others. I have tried several and either regular, original JB Weld works well if you're not bothered by slightly mis-matching colors- and it is actually matches pretty well with gray or black synthetic stocks.. The dedicated kit I like is Miles Gilbert.

Pillar bedding in conjunction with regular bedding is the bee's knees for consistent rifle performance but it is a level trickier than regular bedding without the pillars.

Yes, don't worry about getting the compound into the stock holes- drill them out later. Just make sure your action screws are well coated with release. Control and remove excess ooze-out with shaped and sharpened Popsicle sticks and acetone or alcohol and paper towels.

For wood stocks, you can relieve the split-out problem area around and behind the tang with a 1/16- 1/8" gap and bed that during the process. If you have bedded the recoil lug (s) properly there should be no problem with tang split-out after a correctly done job. The rear surface of the lug (s) should be contact bedded... but not the bottom, sides or front. Put a layer of masking tape on the bottom, sides and front and coat with release when bedding. Go for it and good luck!

Thanks, 8. Follow-up: I know I can still the stock holes back out, but with release agent inside the pillar that is created when the top and bottom metal come together, and releaae agent on the screw, does it matter of epoxy gets in there? Or would the screw just force it out?

 

[sestoppelman]

To answer the above question first about bottom metal. I leave that off the process, just set it aside. As to the trigger removal. I don't remember if I did or not remove it, but if its easy, do it, get it out of the way. Anything you can keep clear of bedding is a good thing.

With spring clamps, I make sure to get one of each side of the rifle to apply even pressure to not get cockeyed. I also eyeball it using the sights to look for lean one way or the other. I know it seems like it now, but it aint rocket science. Should have seen the way I obsessed over my first M1 Garand bedding job. Kept me awake nights! BA's are simple to bed compared to M1's and M14's.

 

[fourfive8]

If I understand the Q, it shouldn't matter. There will likely be compound ooze down around the action screws during the process. If the screws are coated well, they should just turn out of the hardened epoxy without issue. Once removed just drill out the holes to the original diameter for clearance. When pillar bedding the pillars are bedded (glued) in at the same time with full or nearly full metal to metal contact on both the action and bottom metal sides of the pillars. Likewise any compound that oozes down inside the pillar can then be drilled out. The idea is for the action screws to NOT CONTACT the stock if regular bedding or pillars if pillar bedding. The action screws simply hold the action DOWN into the stock and the recoil lugs prevent REAR movement during recoil.

There is an alternate type of "pillar" bedding that simply uses bedding compound as the pillar. The action screw holes are enlarged then the action is glass bedded with the holes filled on purpose. The stock holes are then drilled out for action screw clearance but leaving enough compound to form a pillar made of the compound. Probably not as compression resistant as a metal pillar but certainly better than wood or filled synthetic stock.

 

[clockwork_7mm_gator]

If I understand the Q, it shouldn't matter. There will likely be compound ooze down around the action screws during the process. If the screws are coated well, they should just turn out of the hardened epoxy without issue. Once removed just drill out the holes to the original diameter for clearance. When pillar bedding the pillars are bedded (glued) in at the same time with full or nearly full metal to metal contact on both the action and bottom metal sides of the pillars. Likewise any compound that oozes down inside the pillar can then be drilled out. The idea is for the action screws to NOT CONTACT the stock if regular bedding or pillars if pillar bedding. The action screws simply hold the action DOWN into the stock and the recoil lugs prevent REAR movement during recoil.

There is an alternate type of "pillar" bedding that simply uses bedding compound as the pillar. The action screw holes are enlarged then the action is glass bedded with the holes filled on purpose. The stock holes are then drilled out for action screw clearance but leaving enough compound to form a pillar made of the compound. Probably not as compression resistant as a metal pillar but certainly better than wood or filled synthetic stock.

Thanks, 8. That all makes good sense. But I don't think I'm asking my question very well. The front screw on this particular set up can't make contact with the epoxy or the wood because when the top and bottom metal clamp together, they form a sort of pillar with the screw entirely hooded inside. (You can sort of see it in the second batch of photos above.) So what I was really getting at is whether I need to keep epoxy out of that enclosed area created by the pieces coming together or if release agent inside (and on the screw) and the screw being turned in all the way would force out the epoxy anyway? (I'm still not sure I'm asking this clearly.)

 

[fourfive8]

Thanks, 8. That all makes good sense. But I don't think I'm asking my question very well. The front screw on this particular set up can't make contact with the epoxy or the wood because when the top and bottom metal clamp together, they form a sort of pillar with the screw entirely hooded inside. (You can sort of see it in the second batch of photos above.) So what I was really getting at is whether I need to keep epoxy out of that enclosed area created by the pieces coming together or if release agent inside (and on the screw) and the screw being turned in all the way would force out the epoxy anyway? (I'm still not sure I'm asking this clearly.)

Got it, maybe... I think I know the type action you are describing. It already has a type of "pillar" as part of the design. Should be no issue as long as the top and bottom metal "bosses" that actually are supposed to contact that integral pillar have a good coat of release agent (wax) before bedding. That thin metal pillar was (is) designed to act similarly to a modern pillar by arresting the stock compression from the tightening of the primary action screw. Just like a modern "pillar bedding job", for best result, try to make sure the action screw that passes though the pillar has clearance and doesn't make contact when tightened during the bedding process. If some compound oozes into the tube no issue as long as the screw is well coated. Once set, just separate and remove the screw and drill out excess compound. Since those are usually a fairly hard type, thin walled (possibly split) steel tube it may be a little less forgiving than a modern thick walled aluminum pillar. But should be no large issue as long as you have a drill bit to fit the original ID of the tube.

 

[Stuart Satterlee]

A set of guide screws will keep all of the epoxy out of your action screw holes during the 1st initial steps of your bedding process. A guide screw is a screw with no head on it and is about 3.0 inches in length. Screw a set into the action. Roll up some paper towel and put it in the front screw hole of the bottom metal, install the bottom metal to the stock, run a piece of tape around the bottom to hold the bottom metal in the stock. Lay your epoxy in, grab your barreled action, pull the paper towel piece out our the front screw hole that is in the bottom metal. Insert your barreled action using the guide screws into the stock. Press down on it firmly by hand. Unscrew the guide screws, insert your normal screws and tighten them up enough to finish seating the barreled action to the stock around 40 inch pounds of torque will be all that is needed. The use of the guide pins and rolled paper towel keeps the epoxy from running thru the front hole and it keeps epoxy from going up into the screw hole in the receiver. The use of clay and release agent is well documented thru out this thread so no need to talk about it further. Do a trial run with the guide screws to ensure they slide thru the holes with no jam ups as that can cause for an ad lib change in bedding plans with wet glass in the stock. Smear Vaseline on the out side of the stock this will enable any accidental displacement of glass to come off easily.
Another important detail ensure your barred action fits the stock correctly in the first place.
Black it out with Jarrows inlet black barrel and action, you want contact at the front flat bottom of receiver and the length of the tang. No contact in the middle. I've seen zastava stocks where the front web of the stock is too thin, creating a bad situation where the metal is pulled tight, box and rec. And the stock essentially floats. Removing material from the top of the magazine box allows the metal work to clamp at the front and rear web of the stock. If you have this situation, correct it prior glassing in.

 

[bruce moulds]

the test of a well bedded action is that is as stress free with the screws done up as possible.
to establish this you must have bedded the action correctly such that it can fall out of the stock with the screws undone.
that alone means clearance is required on sides and front of recoil lug.
this is easily achieved by taping these parts, as with the any vertical area of the rear tang.
one way to minimize stressed bedding is to support the barrel in its channel at 2 places, possibly with tape, such that the action sits where it should end up.
rubber bands at the 2 support positions leave the action untouched, and therefore no stress on it .
to test, first make sure the action will in fact fall out.
using a magnetic clamp on the barrel, you can set the probe of a dial indicator to touch the forend about where a sling swivel might go.
with the screws done up, stand the rifle in a chair butt down, and undo the front screw without pressing on the driver.
prober screwdrivers are required with parallel sides.
you can read the dial indicator movement as the barrel moves up and down.
no reading, while ideal, will probably suggest the bedding is binding on the action - a bad thing, because if this happens when the gun is fired it might not return to battery in the bedding, causing double grouping.
0.001/ 0.002" is a good goal.
now tighten the front screw.
a gun cradle is good for this, or across the arms of the chair.
set up the indicator on the action with the probe in the comb or pistol grip. the nearer the tang the magnet the better.
tighten and loosen the rear screw and look at the dial.
some people can put a finger on both the tang and the stock at the same tome and feel movement here.
if you can feel it the action is probably overstressed for best accuracy.
should your job not pass these tests there is only one option.
stert again, and keep doing it until you get it right.
rule no 1 is NEVER tighten action screws until the bedding has fully cured, of you introduce stress.
stock makers screws are ok in the holes as long as the holes are generous diameter for plenty of clearance
it does not matter if bedding goes down the holes, as it leaves a good pilot hole to drill for the clearance required fro good grouping and no splitting of stocks.
with regards release agent johnsons paste wax or shoe polish are good.
once applied you should polish it and it will release well.
put it on properly and in all the right places it the important issue.
bruce.

 

[fourfive8]

Yep, you can use your regular action screws for the bedding process- just don't torque them down tight. One guideline I see often and it seems to work well is to snug them down slowly until you feel contact resistance, then back them out a half turn or so... just enough to take the stress off. You need to start tuning them down slowly to give the compound time to flow and find its own equilibrium. IF using stockmakers headless screws for alignment only... an easier alternative to trying to loop or tie off rubber bands around fore and aft on the action is vetrap. It is elastic and grips to itself so is much easier to use than rubber bands or rubber tubing. Something I discovered a few years ago trying to find a handier alternative to rubber bands or surgical tubing.