Preacherman
Member
In this thread, member DJ E. asked about shortening the synthetic stock of a Kel-Tec SU-16. Well, I've had to shorten a number of synthetic stocks for myself and others, and I thought it might be useful to post a thread on an easy way to do it.
There are two major problems with shortening synthetic stocks:
(a) The butt-plate or recoil pad usually screws into molded bits of synthetic stock, that are fixed in position. If you shorten the stock, often you remove these "sockets", and then have nowhere left to reattach the butt-plate or recoil pad.
(b) You have to be able to get to the stock bolt or screw, so using a filler in the stock can be a problem.
I get around these problems like this.
1. Buy a can of expanding wall-sealant foam (NOT the rapid-expanding stuff - that can crack your stock! Get the high-density, low-expansion stuff.)
2. Determine the width of your stock bolt or screw, AND (very important!) the width of the tool you use to attach/unscrew it. Add about ¼" to the width of the tool, or a bit more if you want more "wiggle room". Example: Say the screwdriver you use on the stock bolt has a head ½" wide (at its widest point). Adding ¼" for "wiggle room" gives a total of ¾".
3. Buy a piece of PVC plumber's pipe or tubing with an INTERNAL diameter at least as great as the width you determined in step 2 above. Buy it long enough to run the length of your stock from the stock bolt/screw to the butt-plate (heck, add a couple of inches for safety - pipe is cheap!
)
4. Buy (or obtain) a couple of pieces of wood big enough to take the screws of your butt-plate or recoil pad. These need not be more than about ¾" square, and about 1" deep. Don't use cheap plywood, though - use something that can take a screw and not split or crack. Drill a hole for the screws of the butt-plate in the face of each block. Put a couple of short nails or screws into the sides of each block, to provide a purchase when the blocks are secured with foam.
5. Now comes the interesting part... First, measure the new length for your stock. Do this with the stock ON the gun... Then, remove the stock from the gun, and take off the recoil pad/butt-plate. Cut the stock to the length you want.
6. Take the pipe you bought in step 3. Insert it through the rear of the stock, and check on how well it fits around the stock bolt aperture. It needs to be a good fit, so if you need to modify the end of the pipe to fit better, do so with a Dremel tool, or a knife of some sort. Make sure that it fits with the stock bolt centered in the pipe, and also make sure that the tool you use to tighten/loosen the stock bolt can fit easily down the pipe and be applied to the stock bolt. (If you get this wrong, you've got major problems later, so take time to do this carefully.) Finally, make sure that the pipe can run down the length of the stock at an angle that is as close to straight-on with the stock bolt as possible - it's hell using a screwdriver if you can't get the end square to the screw!
7. Now, holding the PVC pipe (or securing it somehow) square with the stock bolt hole (see 6 above), use the wall foam you bought in step 1. Spray some into the bottom or "wrist" of the stock, around the PVC pipe where it covers the stock bolt hole. Spray enough to hold the pipe in place - I usually spray it about 2" to 3" deep. When this is done, BEFORE the foam hardens, check to make sure that none of it has got into the PVC pipe - if it has, clean it out at once, so as to prevent future problems.
8. When the foam has set, your pipe should be held at the correct angle in the stock. Without disturbing the foam, use a Dremel tool with a cutting wheel to cut the pipe off level with the rear of the stock. (The reason I recommend a Dremel for this step is that it doesn't put much pressure on the pipe - if you do that, the pipe might loosen in the foam, and you want a reasonably tight fit. If you need to use a saw, rather put more foam in, up to half-way or three-quarters of the way up the stock, in order to provide a firmer hold on the pipe.) If your butt-plate or recoil pad fits slightly into the rear of the stock, you'll need to shorten the pipe a bit more to accommodate this.
9. Now you need to provide a place for the screws holding the recoil pad or butt-plate. Take the two blocks of wood you obtained in step 4, and keep them handy. Fill the rest of the stock with the foam, working slowly to ensure that no air-pockets are left. When you get to within an inch or so of the back of the stock, position the blocks of wood in the right places to receive the screws of the butt-plate or recoil pad, and fill around them with the foam.
10. Use enough foam to fill the stock completely, and protrude a bit above the rear "walls". Let it dry, and then trim it to the proper length with a utility knife. If you need to leave a bit of an "indent" for the recoil pad or butt-plate, do this now, fitting the plate to the stock and removing a bit of foam at a time, so as to ensure a good fit.
11. Take the butt-plate or recoil pad and attach it to the wood blocks with the screws.
There you have it - a shortened stock, which is also stiffer (thanks to the foam filling), with an access channel to the stock bolt, and a firm grip for the recoil pad or butt-plate. Hope this helps!
There are two major problems with shortening synthetic stocks:
(a) The butt-plate or recoil pad usually screws into molded bits of synthetic stock, that are fixed in position. If you shorten the stock, often you remove these "sockets", and then have nowhere left to reattach the butt-plate or recoil pad.
(b) You have to be able to get to the stock bolt or screw, so using a filler in the stock can be a problem.
I get around these problems like this.
1. Buy a can of expanding wall-sealant foam (NOT the rapid-expanding stuff - that can crack your stock! Get the high-density, low-expansion stuff.)
2. Determine the width of your stock bolt or screw, AND (very important!) the width of the tool you use to attach/unscrew it. Add about ¼" to the width of the tool, or a bit more if you want more "wiggle room". Example: Say the screwdriver you use on the stock bolt has a head ½" wide (at its widest point). Adding ¼" for "wiggle room" gives a total of ¾".
3. Buy a piece of PVC plumber's pipe or tubing with an INTERNAL diameter at least as great as the width you determined in step 2 above. Buy it long enough to run the length of your stock from the stock bolt/screw to the butt-plate (heck, add a couple of inches for safety - pipe is cheap!
)4. Buy (or obtain) a couple of pieces of wood big enough to take the screws of your butt-plate or recoil pad. These need not be more than about ¾" square, and about 1" deep. Don't use cheap plywood, though - use something that can take a screw and not split or crack. Drill a hole for the screws of the butt-plate in the face of each block. Put a couple of short nails or screws into the sides of each block, to provide a purchase when the blocks are secured with foam.
5. Now comes the interesting part... First, measure the new length for your stock. Do this with the stock ON the gun...
Then, remove the stock from the gun, and take off the recoil pad/butt-plate. Cut the stock to the length you want.6. Take the pipe you bought in step 3. Insert it through the rear of the stock, and check on how well it fits around the stock bolt aperture. It needs to be a good fit, so if you need to modify the end of the pipe to fit better, do so with a Dremel tool, or a knife of some sort. Make sure that it fits with the stock bolt centered in the pipe, and also make sure that the tool you use to tighten/loosen the stock bolt can fit easily down the pipe and be applied to the stock bolt. (If you get this wrong, you've got major problems later, so take time to do this carefully.) Finally, make sure that the pipe can run down the length of the stock at an angle that is as close to straight-on with the stock bolt as possible - it's hell using a screwdriver if you can't get the end square to the screw!
7. Now, holding the PVC pipe (or securing it somehow) square with the stock bolt hole (see 6 above), use the wall foam you bought in step 1. Spray some into the bottom or "wrist" of the stock, around the PVC pipe where it covers the stock bolt hole. Spray enough to hold the pipe in place - I usually spray it about 2" to 3" deep. When this is done, BEFORE the foam hardens, check to make sure that none of it has got into the PVC pipe - if it has, clean it out at once, so as to prevent future problems.
8. When the foam has set, your pipe should be held at the correct angle in the stock. Without disturbing the foam, use a Dremel tool with a cutting wheel to cut the pipe off level with the rear of the stock. (The reason I recommend a Dremel for this step is that it doesn't put much pressure on the pipe - if you do that, the pipe might loosen in the foam, and you want a reasonably tight fit. If you need to use a saw, rather put more foam in, up to half-way or three-quarters of the way up the stock, in order to provide a firmer hold on the pipe.) If your butt-plate or recoil pad fits slightly into the rear of the stock, you'll need to shorten the pipe a bit more to accommodate this.
9. Now you need to provide a place for the screws holding the recoil pad or butt-plate. Take the two blocks of wood you obtained in step 4, and keep them handy. Fill the rest of the stock with the foam, working slowly to ensure that no air-pockets are left. When you get to within an inch or so of the back of the stock, position the blocks of wood in the right places to receive the screws of the butt-plate or recoil pad, and fill around them with the foam.
10. Use enough foam to fill the stock completely, and protrude a bit above the rear "walls". Let it dry, and then trim it to the proper length with a utility knife. If you need to leave a bit of an "indent" for the recoil pad or butt-plate, do this now, fitting the plate to the stock and removing a bit of foam at a time, so as to ensure a good fit.
11. Take the butt-plate or recoil pad and attach it to the wood blocks with the screws.
There you have it - a shortened stock, which is also stiffer (thanks to the foam filling), with an access channel to the stock bolt, and a firm grip for the recoil pad or butt-plate. Hope this helps!
