which bedding compound?

[cohunt]

I have bed well over 100 rifles in the past 35 years. For my current bedding process, that I've been using for the past 14 years, I use JB Weld "Steel" slow set, to install the aluminum pillars ONLY, a day or so before proceeding with the bedding job. I use Score-High Pro-bed 2000 mixed with 25% by volume Brownells atomized stainless steel powder, for the bedding. I buy the Pro-bed straight from the Score-High site, in two 16 oz kits at a time, one brown and one black. It is relatively thick, and stays in place well, produces an excellent bedding that is rock solid, extremely hard and highly resistant to compression. It's the best bedding material mix I've ever used, and I've used; Brownell's Acraglas (both the liquid and the gel), Brownell's Steel Bed Kit, Marine-Tex and Devcon 10110. When I find something better, I'll switch to that.

The Pro-bed 2000 comes with a wax based releasing agent that speads easily by finger and works excellent. It is much like clear shoe polish but, works better. The releasing agent is a little tough to remove from the action but, coat it with mineral spirits and let it sit for 5 minutes, and it will wipe right off.

DO NOT fully bed your lite barrel! Your bullet impact point will climb as the barrel heats up, more because of the barrel taper and heat expansion lengthwise against the fixed bedding, than the barrel diameter change due to heat expansion! NEVER bed a sporter weight barrel or liter, beyond the straight portion of the barrel in front of the receiver. The only barrels I ever bed beyond the receiver are the heaviest contour, very long match barrels, and only the straight cylinder portion just in front of the receiver, for no more than 2-1/2". If you don't bed that area with extremely heavy long barrels, they will usually sag and affect accuracy.

Best of luck with your bedding job. PM me if you wish to discuss my method in detail.
Kevin

Melvin at NULA full length beds their lightweight barrels -- most claim 1/2 moa from a nula rifle.

 

[ntsqd]

I think that's a discussion that won't be resolved until well after the cows have come home.

I'd like to know what the difference(s) are between a FL bed that shoots well and one that doesn't. I suspect that there's more to it than just who did the work. The Engineer in me would really like to know this, but I don't see myself executing the necessary experiments required.

 

[Alibiiv]

I have been using Brownell's Accraglas 2 gun bedding kits of years. I have had good results with the product, however I am thinking of using their gel for my next rifle. I find that the regular Acraglass is really runny, and....can manage to get in to places where you don't want it to get no matter how careful you are with damming the voids. I use the green release agent, plus I use their spray release agent just before setting the action into the stock.

I relieve at least 1/16th to 1/8th of an inch between the action and the wood where I want the bedding material to set, especially around the barrel and recoil lug. I clearance the wood away 4 inches in front of the recoil lug, as well as under the recoil lug. All of my rifles are Ruger 77s, they have a fairly large flat under the recoil lug, I use a Dremel tool with a spiral cutter to relieve the wood underneath the recoil lug as well as on the sides. There is an attachment in the Dremel kit that goes on the end to make the tool like a router. I super glued a 6 inch long by 2 inch wide piece of clear plexiglass to the bottom of this attachment making the tool into a mine-router. I will carefully use a 1.2 inch round drum sanding attachment when relieving the wood as I relieve the barrel channel. I always make sure that the drum is turning into the barrel channel and not toward the outside, otherwise the sanding drum can, and trust me will grab and gouge the channel; voice of experience!!. I recently have been bedding the entire barrel channel, floating the barrel just 4 inches in front of the recoil lug by using Brownell's "bed master tape" putting two layers of the tape on the barrel. When the barrel is removed from the stock there's a nice .020 thousandths inch clearance space between the barrel and the stock the entire length of the barrel channel. The bed master tape is .010 thousandths thick, I put two layers on at the same time by laying one layer out on the bench and then laying the second layer on top of the first one. Always try to trim the end of the tape going near the recoil lug square for appearances using a razor knife. I use regular isopropyl rubbing alcohol to remove the green release agent with good results. SMK1000plus has some really great information about bedding the straight section of the barrel on a wispy barrel, never thought of the barrel heating, swelling and changing POI. Great info, thanks.

 

[cohunt]

Yes, the full length bed vs free float is a very touchy/subjective area ---but I like to see actual results from those that have done it, rather than just speculation. Obviously it can and does work if people like Melvin are doing it on their custom rifles. It seems like all the internet talk is that freefloating is the only way to go, but that is obviously not true.

From my understanding, pencil and super heavy/long barrels seem to benefit from full length bedding, (keeps harmonics/whip to a minimum with pencil, and helps support droop/receiver flex in heavy ones) most other profiles stem to like free floating--- but those are generalizations and I have no hands on data with full length bedding.

I can tell you that this rifle originally had the pressure point on the stock forearm-- but it was ground off by a previous owner before I could try it -- so it came to me free floated--- when free floated, it would occasionally shoot a 3/4 moa group but it was usually in the 1.5moa area. I used playing cards to add pressure at the tip of the fore end and it now shoots 3/4 moa as long as I keep my barrel cool-- when that pencil barrel heats up at all it starts to wander. BUT the stock is the original remington Tupperware stock, not the bell and carlson fiberglass one (hence the reason I'm replacing it) and as temperature rises the stock gets soft too(cant be helping accuracy)

I will probably start be free floating the barrel and if accuracy is degraded I will try the forearm pressure again to see if it improves.

Once the bedding compound is set and hardened, can you add more at a later date? (Like bedding the barrel) If so do I need to grind the old down a bit for new to "take a bite" correctly?

 

[ntsqd]

I would grind back a little if some additional bedding is to be added. My reason for doing this is that what it there was in contact with a release agent, the skin of the bedding material likely has a little release agent in it and getting a good bond won't likely happen.

 

[SMK1000plus]

Yes, the full length bed vs free float is a very touchy/subjective area ---but I like to see actual results from those that have done it, rather than just speculation. Obviously it can and does work if people like Melvin are doing it on their custom rifles. It seems like all the internet talk is that freefloating is the only way to go, but that is obviously not true.

From my understanding, pencil and super heavy/long barrels seem to benefit from full length bedding, (keeps harmonics/whip to a minimum with pencil, and helps support droop/receiver flex in heavy ones) most other profiles stem to like free floating--- but those are generalizations and I have no hands on data with full length bedding.

I can tell you that this rifle originally had the pressure point on the stock forearm-- but it was ground off by a previous owner before I could try it -- so it came to me free floated--- when free floated, it would occasionally shoot a 3/4 moa group but it was usually in the 1.5moa area. I used playing cards to add pressure at the tip of the fore end and it now shoots 3/4 moa as long as I keep my barrel cool-- when that pencil barrel heats up at all it starts to wander. BUT the stock is the original remington Tupperware stock, not the bell and carlson fiberglass one (hence the reason I'm replacing it) and as temperature rises the stock gets soft too(cant be helping accuracy)

I will probably start be free floating the barrel and if accuracy is degraded I will try the forearm pressure again to see if it improves.

Once the bedding compound is set and hardened, can you add more at a later date? (Like bedding the barrel) If so do I need to grind the old down a bit for new to "take a bite" correctly?

No "speculation". MY experience! No once, but over a half-dozen times on light, to sporter weight barrels over the years. The only times I haven't had the POI climb is when I left the heaviest tapered area(s) of the barrel relieved and only left bedding againts the last <6" of the muzzle end of the stock. The climbing of POI on fully bedded lightweight barrels was usually relatively consistent for each progressive shot within each group, and would stabilize after the barrel heated up and the temperature became somewhat stable, usually around 8 to 10 rounds. It was usually consistent enough that you could predict the shift and compensate for it, but it was substantial, typically around 2" to 4 of total shift, at 100 yards.

On lightweight/featherweight barrels, I leave the barrel completely free floated, develop a load for it and see how it performs with groups 5 rounds. If I don't see decent sub-MOA groups, I'll bed a light neutral/pressure point at the last 3" of stock forearm and test grouping again. Sometimes that helps, sometimes it will make the groups larger and will have to be relieved... Just my experience. YMMV
Kevin

 

[ericbc7]

Deacon and Hornady one shot is the way to go

 

[Steve Watson]

Aces glass with Aluminum pillers

 

[Danehunter]

Many have very successfully user MARINE TEX (gray) because it does not shrink, is impervious to water and is very strong, especially in compression at 13,000 psi.


Years ago I supplied it to my gunsmith for bedding my .300 Win mag Browning A- Bolt's laminated thumbhole stock. Works great.

Eric B.