I am going to attempting my first bedding job. It will be on a Remington XCR stock. Has anyone beddded this stock before? Here are my questions. (I have searched without luck)

The fore stock has the plastic webbing. There is a longintudinal rib from the the lug forward with voids on either side.
1)Do I just bed the narrow rib or do I fill in the voids on either side?
2)If I should fill in the voids should I use small blocks of some other material to take up some room or fill completely with bedding material.
3)There are also two small stand-offs towards the front of the stock. I assume these are for forward pressure on the barrel. Should these be removed?
4) what is the best way to get the nice clean (unseen) bedding at the chamber and lug that is seen on the professional jobs?

Thanks for you help

quote:

Originally posted by Fbull:
I am going to attempting my first bedding job. It will be on a Remington XCR stock. Has anyone beddded this stock before? Here are my questions. (I have searched without luck)

The fore stock has the plastic webbing. There is a longintudinal rib from the the lug forward with voids on either side.
1)Do I just bed the narrow rib or do I fill in the voids on either side?

2)If I should fill in the voids should I use small blocks of some other material to take up some room or fill completely with bedding material.
3)There are also two small stand-offs towards the front of the stock. I assume these are for forward pressure on the barrel. Should these be removed?
4) what is the best way to get the nice clean (unseen) bedding at the chamber and lug that is seen on the professional jobs?

Thanks for you help

You are describing one of Remington's tupperware stocks with the ribs and voids. The ones I have seen are the HS Precision stock. The stock on Remingtons web site shows the HS Precision stock. They have the aluminum bedding block in the action area and are solid through the forearm.

If yours is the typical black plastic stock, then I don't recommend bedding them. Bedding material doesn't stick worth a shit crap and they are way too flexible.

On these stocks, I recommend free floating the barrel by a "large" margin to keep the forend from ever coming into contact with the barrel. You can test the amount of float needed by smacking the forend with the palm of your hand. If you can hear or feel any contact with the barrel, keep cutting.

The answer to question 4 is careful preparation and lots of practice.

Happy New Year!

Wespac
Thanks for you reply. A coule more questions and comments to your post.
My stock just has the webbing and no aluminum bedding block
I have read that scoring and or drilling small holes in the bedding area helps with adhesen to the plastic. Do you agree.

Thanks and Happy New Year!

Would it not help because the stock is so flexible?

quote:

Originally posted by Fbull:
Wespac
Thanks for you reply. A coule more questions and comments to your post.
My stock just has the webbing and no aluminum bedding block
I have read that scoring and or drilling small holes in the bedding area helps with adhesen to the plastic. Do you agree.

Thanks and Happy New Year!

Would it not help because the stock is so flexible?

No. Drilling holes at various angles may help keep the bedding in place but frankly I wouldn't waste the time. Seriously. I have seen guns wearing these stocks shoot very well without doing anything more than free floating the barrel. You can go crazy and add pillars but the stock is still going to flex. But it would provide good practice.

Good luck!

As I'm unfamiliar with these stocks I would like to know what the stock material is made of .

Westpac ; Do you know if they're polypropylene or injection molded Nylon ?.

I've heard reference to tupper ware however doubtful if that's actually the plastic used .

Simply curious . Thanks . Doc

I did a little surfing and came up with this .

Assure your Remington rifles and shotguns maintain their legendary accuracy and are not affected by the elements with the all-weather consistency of a nonglare fiberglass-reinforced synthetic stock. Remington XCR stocks are made to handle reliably under the harshest conditions. The XCR stocks feature a Limbsaver™ R3® recoil pad and Hogue rubber overmolding on the grip and forend for sure grip in slick conditions. Fits Remington Model 700 actions only.
Available: Short-Action, Long-Action and Magnum models.
Colors: Black or Camo.

So they are Fiberglass correct !. Acetone cleaning and Scoring would be in order followed by

an Epoxy Not acraglass for bedding stability .

However Westpac would know better as it's his business to know , I only know materials compatibility .

I don't know what the material is, perhaps ABS. It resembles the material that the box is made from that Glock pistols come in. If there is any fiberglas in this stock, it has to be some new stuff that looks and cuts just like plastic.

Here are some interior pictures of an XCR I have in the shop.

SMC Fiberglass acts like that It's what's used on Corvettes body's and MANY other applications .

This is why I recommend Acetone wiping then Scoring and using Epoxy rather than polyester

( or Fiberglass Resin ) Epoxy will hold to almost anything yet very little will adhere too Epoxy it's self .

Sheet Molded Compound is a process well allow me to Plagiarizer , it just saves me time !.



What is SMC?
SMC is the abbreviation for Sheet Molding Compound. Today it is the most important glass fiber reinforced composite material. Parts made of the economical thermoset SMC prepregs are well accepted in the market. Complex shapes with slugged walls, little radius, multiple spline and inserts are possible. The unsaturated polyester resin is the matrix material. The cross-linking reaction of the thermosetting polymer during the compression molding makes the shape of the component part possible.
principle of cross linking reaction with unsaturated polyester

Technical process
[Link: Get additional information about the glass fiber production] The SMC production can be divided into two processes - the SMC prepreg production and the SMC compression molding.

The SMC prepreg production
Glass Rovings are used for the economical thermoset SMC prepregs. They are re-spooled and cut to a length of 10 - 50 mm (see Fig. 1). The fibers fall on a foil coated with a paste of unsaturated polyester resin. Combinations with continuous fibers are possible. After covering with a second foil on the top the packet runs through a roller drawing frame. In this step the fibers are impregnated with a resin matrix, so that every filament is encapsulated by resin. The semi-finished product can be wound up or cut to plates of specific dimensions. The storage time depends on the recipe and varies from a few days up to a couple of weeks. The prepregs are processed with compression molding. Table 1 shows a typical recipe. It can be varied to meet specific requirements such as class-A-surface, hot-wet resistance or high tensile strength.
typical SMC recipe

The SMC compression molding
First of all the covering foil must be removed from the prepreg. Then, the right weight of prepreg has to be put in the correct position in the open mold. The mold is closed and heated up to a temperature of 150°C. The press load is about 10 MPa. Fig. 3 shows the viscosity-time profile of SMC. On the left side you can see the viscosity increasing during the aging process. On the right side is the viscosity during the compression molding. First, the resin viscosity is decreasing due to a higher temperature. The resin flows and fills the cavity. Because of the high temperature, the cross-linking reaction rate rises to a maximum. Therefore the resin viscosity now grows. After the reaction - the time depends on the size of the part - the mold is cooled down to room temperature. Now, the part is removed from the mold. The compression molding can restart.

SMC-Process

Viscosity during the SMC process

Advantages of SMC technologies
The use of glass fibers as a reinforcement leads to the production of strong and cost- efficient parts. Their relatively low specific weight (density 1,6 - 2,1 kg/m³) offer weight saving effects.
SMC parts are non corrosive and have a long lifetime. Due to good formability during the compression molding process slugged walls, little radius, multiple spline, bosses or inserts can be considered.
Design flexibility, excellent dimensional stability and short lead time in production and the possibility of recycling are some reasons for the SMC product acceptance.


A Typical ; PROPERTIES TEST
METHOD
ASTM GLASS CONTENT

22% 30%
Flexural Strength, psi D790 18 - 22,000 24 - 28,000
Tensile Strength, psi D638 7 - 9,000 10 - 14,000
Compressive Strength, psi D695 20 - 25,000 25 - 30,000
Water Absorbtion, % 24 Hours @ 23° C D570 0.2 0.2
Impact Strength, Notched izod ft/lb./in D256 6 - 8.0 10 - 12.0
Heat Distortion, °F @ 264, psi D648 350 350
Specific Gravity D792 1.7 - 1.9 1.7 - 1.9
Shrinkage - Mils/in. 1 - 3 * 1 - 3 *
Dielectric Strength, v/mil, Perp, ST, in oil D149 320 320
Arc Resistance, Sec. D495 120+ 120+


I would bet that's exactly what it is WestPac , knocked out fast and relatively clean .

FYI ; Some will have Kevlar and or Spectra Carbon fiber and the likes in them ( H&S Precision - Kevlar )

I agree with epoxy bedding,I use Devcon.I had a release problem so I called Dupont and they recommended their release just for their epoxy and I ordered some and had super results.
Also I bedded several Remington XCR stocks,1 for myself and 4 for friends.I also pillar bedded 2 Weatherby Vanguards with the cheap stock,sanded the seam lines out and painted the stock and have had no problems.Filling the web voids will add too much weight to the XCR stock.
As mentioned sand out the contacts at the end of the forearm and free float it well.That XCR stock I had started to flex after alot of shooting and I had to go back and take more surface out of the channel.
I have seen someone use that expanding insulation you spray on to fill the voids and then paint it.Someone mentioned a new stock,that would be my choice.I do have issues with the aluminum bedding block in my Bell & Carlson Medalist stock for my Weatherby Vanguard stock,it transmits recoil to shooter way too much,I can't shoot it with 300 Weatherby mag more than a few times before I have to quit.They are probably more accurate but I like the Knoxx stock in heavy recoil rifles,they are like my wifes people,not too good looking but they work extremely well.Drop-Shot

Typically when you here "fiberglass reinforced composite" It means Glass Reinforced Nylon. Varying degrees of make up it is the same stuff that they make glock and HK frames out of. Granted their own proprietary mix. But the heart or the matter is adhesion and nylon being a oil retaining plastic like delrin, and polypropylene. The oils that are in these plastics comes out over time and prevents most adhesives from staying put. Build in the fact that you will subject the joint to shock load and vibration adds to the problem.
PVC and ABS have one advantage over the other plastics and that is solvent weldability. The correct glue will stick to these but It is my firm belief that these lower cost stocks are nothing more then glass reinforced nylon.
The only way you could hope to adhere a resin to the material is to build in mechanical locks like tapers and dove tails and even then it wont be that great.
Personally I'd invest in a new stock of wood or 100% fiberglass/resin/kevlar mix but no glass reinforced injection molded parts.

kcstott ; Typically when you here "fiberglass reinforced composite" It means Glass Reinforced Nylon

Not necessarily as there are so many different " Fibers " which can now be used and

their all suspended in these cases a Resin of Polyester matrix .

Nylon as you've pointed out does not adhere well with polyester . I would be surprised

if Nylon is used in these applications .



I'm curious as to what is meant by the following statement . By ; Drop-Shot

That XCR stock I had started to flex after alot of shooting and I had to go back and take more surface out of the channel.

How was the stock flexing ?. The above picture provided by WestPac ( Very Good I might add )

Shows a longitudinal spline with cross rib reinforcements which should provide Excellent

rigidity . So I'm most curious as to what is failing to retain shape ?.

I have never fooled with one of these stocks and I'm not questioning anyone other than

for the knowledge of understanding their particular short comings !.

I have other synthetic stocks I have worked on. Some with issues others with out .

I also use and prefer Devcon Epoxy products IMO they are some of the Finest available too the GP .

For filling the voids, I used some high density foam that you can cut with a knife to fit. Packing "peanuts" will work if you can crush them so that they will not push themselves up into the barrel channel itself before the bedding compund hardens. I have done this and it works well.

I have also used Honeycomb foam core as fillers of voids over coated with epoxy or Acarglass .

While Styrofoam works with epoxy it will NOT work with any polyester based resins .

However Urethane foam core in unaffected by Polyester saturation . In regards too degrade .

quote:

Originally posted by Doc224/375:
kcstott ; Typically when you here "fiberglass reinforced composite" It means Glass Reinforced Nylon

Not necessarily as there are so many different " Fibers " which can now be used and

their all suspended in these cases a Resin of Polyester matrix .

Nylon as you've pointed out does not adhere well with polyester . I would be surprised

if Nylon is used in these applications .

Well I beg do differ.
Any injection molded stock is not using a Resin at all. I should have stated that I was referring to an Injection molded part. I can see ejector pin marks on his stock so I'm assuming it's injection molded.

An Injection molded "fiberglass reinforced composite" is in fact glass reinforced nylon in 99% of the parts that are made. Nylon comes in a wide variety of grades, durometers, and strengths. and the amount of glass can be varied to suite the part.

As for other Fiberglass composites yes you're correct there can be many different type of fibers and all are in a polyester base resin.
But not all rifle stocks are molded of polyester resin and glass/kevlar/carbon fiber.
Some inexpensive stocks and quite a few pistol frames are an injection molded nylon part of a given amount of glass reinforcing.

Every polymer frame on the market that I know of is a variation of glass filled nylon

I do not think that anyone has come out and said that to hold the Devcon in, I drilled angled holes, completely though, from the recess behind the recoil lug recess. When bedding, I made sure that the Devcon passed through the holes.

This could be used anywhere you want in the stock, to lock the bedding in, along with angled blind holes and degreasing. It has held for over a year on a Rem 700 chambered for the 300 Win Mag.

Do not forget a couple of layers of tape, I like the blue painters tape, on the front and sides of the recoil lug!

Forgot, the two stand offs!

Try leaving them on, if the rifle does not shoot well, you can knock them off later with a rat tail file and do away with the up pressure on the end of the barrel. Mine shot well with them on, so they will stay.

KcStott Posted

Well I beg do differ.
Any injection molded stock is not using a Resin at all. I should have stated that I was referring to an Injection molded part. I can see ejector pin marks on his stock so I'm assuming it's injection molded.

An Injection molded "fiberglass reinforced composite" is in fact glass reinforced nylon in 99% of the parts that are made. Nylon comes in a wide variety of grades, durometers, and strengths. and the amount of glass can be varied to suite the part.



Mr. KcStott ; What is injected if it's not a resin ? A liquid binder or thermoset resin matrix

Old fashion methods use granules pellets of plastics heated or thermoset in platens .


Since its invention in 1872, the injection molding process and the plastics industry has become a multi-billion dollar industry, with 32% of all plastics, by weight, processed by injection molding. Injection molding has made possible the cheap and durable construction of many consumer and industrial items that have had a profound impact on society.

At Plastic Injection Molding Resource, our goal is to educate consumers and engineers by providing information regarding manufacturers, resins, materials and anything else related to injection molding.

I can also further assure you that 99% of parts are NOT Nylon Glass Filled !.

You have also stated ;

As for other Fiberglass composites yes you're correct there can be many different type of fibers and all are in a polyester base resin.

Many fiberglass composites in fact utilize ; Aniline , Polymers and Many Many other resins .


Aniline-modified epoxy resin which contains tertiary amine in the middle of the polymer chain was synthesized by the reaction of aniline and epoxy resin. The resulting aniline-modified epoxy resin and two commercial epoxy resins with different epoxy equivalent weights were reacted with 2-ethylhexanol-blocked toluene diisocyanate (2-EH-blocked TDI) to obtain thermally crosslinkable epoxy resins. These epoxy resins were subsequently reacted with various secondary amines and partially neutralized with acetic acid to give thermally crosslinkable cationic resins. The resulting cationic resins were dissolved in suitable solvents and mixed with deionized water to form emulsions. The crosslinking properties, emulsion, and electrodeposition properties of these resins were studied in some detail. The electro-deposition yields of the emulsions prepared from aniline-modified epoxy resins were higher than those of other emulsions. The crosslinked films prepared from aniline-modified epoxy resins were also glossier than those prepared from commercial epoxy resins. High deposition yield and high glossiness were the characteristic properties of the aniline-modified epoxy resins. Thermal properties were not affected by aniline-modified epoxy resins.


The structure of composite materials is well known - essentially, fibres are bonded together in a particular orientation by a polymer matrix, which transmits loads to the fibres and protects them from damage. The three main types of fibres currently used are glass, aramid and carbon. Research into the use of composites for construction related applications is mainly looking at preimpregnated materials, or ‘prepregs’, which should not be confused with traditional GRP or glass reinforced polyester materials.

Politely as I can ; I have worked in this field for many years as a Chemist, a PhD. in Organic chemistry

along with a M. Structural Engineering ; Your simply Mistaken in your assumptions .



This is hardly the time or place for a lesson in composites technologies .

As I originally stated .I'm unfamiliar with this particular stocks construction or materials .

There for I'm unable to give a definite answer as to what would be the best method of adhesion

for bedding this stock . However please keep in mind that the vast majority of

" Composite Gun Stocks " pertaining too Rifles are bed able .