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I just got my boyds stock in yesterday. I'm sure it's been done before, but I want to add longer pillars for better contact and the bed them in. I took out the old pillars form the stock's stock,lol. But the front pillar isn't long enough and is about maybe 1/4" short. Does anyone know of any pillars that would work for this project with a little drilling of the boyd's stock if necessary??????
Well, looks like lamp rods. But what size????
I picked up some lamp rod the other day to do this same thing this week end. I picked up a package of 2 pieces that are 3" long but can remember the diameter and threw the packaging away.
Maybe 3/8"
The are some great how too's buried in the forum. Best results seem to come (after drilling out the factory pillars) from drilling a slightly larger hole then your pillars. Say 1/2" for 3/8" rod. Bolting your pillars to the action and performing bedding and pillars in one process. Not forgetting to pull the recoil lug and also bedding it with the action. Preventing it from sitting to low and allowing recoil to jump the lug. (Learned this the hard way). Results can be as bad as a split stock.
Good drill bits such as forstener can minimize risk of splitting or chipping the stock when drilling. As others have said the first one is nerve wracking. Use a ton of release agent and maybe a little clay and should pop out with a firm whack when cured.
Google Ernie The Gunsmith, he has aluminum pillar rod in 3/8'' & 1/2''. Plus great info on bedding.
lamp rod from Home Depot or Lowes comes in 2 pack about 12" long i think. it's 3/8" O.D.
Bruce
I did something like this for my Leopard stock on the 17hmr. http://www.rimfirecentral.com/forums...d.php?t=151960
You can find other brass fittings in the plumbing dept that work as well. I used a drill press and file to clean it up and get the size just right.
Lamp rod is threaded with an untapered pipe thread, so it'll be roughly the same outer diameter as 1/8" schedule 40 pipe (0.405" OD) but smaller because it's threaded. I just use a length of unthreaded brass pipe because it's easy to cut with one of those hand-powered pipe cutters and, oddly, cheaper than steel or aluminum.
Just started working on my .243 in a Boyd's Prairie Hunter after reading as many threads as I could find. I did buy some JB Weld, but really haven't got the nerve to bed the pillars quite yet. I used a lamp rod and a dremel with a cutting blade to do the chopping and it worked out fine. Luckily there was no original pillar for the back action screw - just the hole. Initially, I had dremmeled out some wood inside the stock as the fitting was not very good at all - the action sat much to high in the stock as it came out of the box.. For me, this was hit and miss because it was all guesswork about where and how much to take off. I couldn't get it sitting right in the stock so that the safety tang would not bind and the barrel would float. So pillars seemed to be the next step.
I put a number of winds of black tape around the barrel at the front of the stock - wanted to make sure the barrel would be floating.
Front pillar. I left the original front pillar (eschution?) in. The top was down about a 1/2" from the top of the stock barrel and the hole was big enough for the lamp rod to slide in. I cut a length of rod that sits on top of the front pillar and comes up to even with the stock barrel where it contacts the action. So the front pillar is in two parts. Didn't touch the recoil lug embedded in the Boyd's stock and the action seems to be fitting into it o.k.. Not sure if the rod has to reach higher. If the action bolt is tightened to much, then the barrel touches the wood stock. If the rod is to high, the action does not sit right at the back nor in the recoil lug. The original action bolt seems to work o.k. for length for now.
Back Pillar. There was no pillar that had to be removed - just a hole. To enlarge the hole to fit the lamp rod, I started with a small drill bit and went through increasing sizes of bits until the hole was large enough for the rod. Luckily only a very little bit of wood chipped off on the top end so the hole ended up clean. I cut a length of rod to fit from the bottom of the trigger guard up through the stock and about 1/2" above the barrel stock. Tried 3 or 4 lengths to see what seemed to be a good fit. The problem seemed to be to get action sitting so that the tang safety would function well and get the action seated so it looked proper. Sitting to low, the safety would bind. Sitting to high just did not look right.
The rear action bolt was to short and I had picked up a longer 6 Metric bolt from a hardware store (same thread as action). I tightened it down very firmly to the point where the trigger housing moved up (spring loaded) and everything was tightened up. If the bolt is to long, it will go right up through the hole in the action and block the bolt. When tension is loose, the tang safety would function but ride high. If tightened to much, the safety would jam on the stock and bind. Not at all sure about the trigger housing that has the "spring action" and why this is even necessary. This must create a problem if stock bedding is going to be done.
The rifle seems ready for test firing to see how it shoots. Still not happy with the barrel float. It is just barely touching the stock at the very front end but otherwise it is floating. May have to dowel/sandpaper on the stock a bit. The tension on the front action bolt is firm but nowhere near the recommended (by Boyd's) 35 in. lbs. To do this would have the barrel firmly resting on the wood stock. Once I know everything fits properly and it shoots well, I will bed the pillars with JB Weld. Not sure I know enough to try to do a stock bedding. The spring trigger housing strikes me as bothersome in terms of where to put the bedding.
A work in progress, but it may be helpful to someone thinking about doing the same thing. Any thoughts or comments, + or -, about what I have done so far will be appreciated. There is still time to make changes.
Thank you 22BV for that write up as it was very informative to me........I picked up some lamp rod today from Home Depot 1/8 size, but the factory action bolt heads are just a smedge bigger that the hole. I'm afraid the bolt head will sink in the rod if I attempt to torque to specified settings. So I have two more questions.
1. Should I use the 1/8 lamp rod I have or go bigger or smaller?
2. What size bolt fits my 270 action?
It's fine. Wrap your action screws (or studs) with a bit of tape so they're centered in the pillar.
Oops, I misunderstood. The action screw at the back is supported by the trigger guard, so no need to worry about it. The front action screw is more tricky, but different people have different solutions. I used a steel spacer I picked up at a hardware store and counterbored. It got epoxied in place when the pillars did. A flat washer could have done the same job.
Still, the action screws are 1/4-28.
I think the current stocks are all using plastic. With the steel I think the short extension works ok. Not sure it would have the desired effect mating to the plastic one.
The 3/8's od rod will have good fit for the 1/4-28 screws. If you full pillar through the plastic magwell a longer screw will be needed.
If you aren't comfortable doing the pillars consider just skim bedding the action to get a supported fit.
So go with 3/8 instead of 1/8 threaded?
newsshooter,
I read your how to from the link your provided. I noticed you said the brass was easy to work/cut with due to it being soft. So with that being said. Is it possible for the brass to compress or warp from the torque on the action bolts?
Potentially. The yield strength of brass is about 29,000 psi.
Well it is easier to cut, file, shape over steel. That being said the torque spec for my 6.5 Creedmoor is 65 inch lbs, divide that by 12 and you get 5.416 lbs. Don't think that is enough to cause a problem. I'm sure it is stronger than an XX75 arrow shaft. I think it is as thick as lamp rod and already has a larger platform so you don't need a washer on top. I made sure the inner diameter had enough clearance for the bolt and counter sunk the head of the pillar using a forstner bit. Epoxied it in place, since the bolt is compressing the pillar and not the wood I think it will be fine.Quote:
Originally Posted by Bodydub
How is 5.4 lbs torque enough to compress or warp a substance with a yield strength of 29,000 psi?Quote:
Originally Posted by DrThunder88
Well, 5.4 lbs (in-lbs, I assume) on a 0.25in steel screw generates an axial clamping force of 108lbs. So, I suppose if the contact patch between the round receiver and the flat pillar is about 0.003 square inches, it would generate sufficient pressure to exceed the yield strength.
Still holds well. But will admit so does my 500/375 only skim bedded. It was notorious for recoiling loose before bedding the recoil lug and action in its previous life as a 7RM. No pillars yet.
65 in-lbs or 5.4 lbs, what is the equation for determining that it would exceed yield strength? Also if the action were bedded how would that affect it since the contact patch would be much larger? I'm also guessing that if the pillar deformed at all the contact patch would get larger, at what point would the increase in contact patch reduce the pressure enough so that it wouldn't exceed the yield strength of a brass pillar?Quote:
Originally Posted by DrThunder88
While checking out my rifle after doing pillars/putting into a Boyd's stock and doing dry firing, I found that when I tightened down the action screws firmly (not anywhere near 35 "/lbs), cycled the bolt, and then pressed down hard on the safety tang - the firing pin fired. Not good. The action seems to be seated well, and the trigger functions as it should and the tang safety is working fine for off/on switches, yet there is something very wrong. When tightened very firmly, the tang safety locks up and won't move either way.
Anyone else running into this, and if so - what seemed to be a fix?
Edges of the sear touching? Or bolt release? Hard to see had some do that. Relieve the stock all was good.
Thanks, Six. Happy to know that it does happen from time to time. I decided to try a different route with the action off of the stock.
Rear Action Bolt:
I used a 6M bolt that I thought was the right length - put it through the pillar - & into the action (with the bolt out) so I could see the head of the bolt coming through after tightening down very firmly from the bottom. This way it was steel to steel and very firmly in place. I estimated how much to dremmel off the upper end of the bolt - the amount that was sticking through the floor of the action plus a tiny fraction just to make sure that when tightened, it would not come through and interfere with the bolt when installed in the stock. I tried the original bolt but for some reason it did not work - I still got the pin dropping by pressing down on the tang safety. Back to the 6M bolt and it worked fine. Go figure.
By pure coincidence, after taking off a bit from the bolt, the bolt ended up to be the same length as the original action bolt from the old stock. Hopefully the original bolt will work as the 6M from a hardware is just a tick sloppy in the threads.
The trigger unit is held in place by two pins starting from the side opposite the bolt. They fall out easily and don't ask me how I know :( Luckily they just dropped out on the carpet below my work station. I can see why the current thought is that replacing the trigger unit is a piece of cake. This unit is spring loaded and the unit must be sprung up and tight to the receiver bottom. I tested this with the action off by putting the rod over the action bolt, inserting through the trigger part, into the receiver bottom (bolt out) and tightening it down to more than firm. The trigger unit was tight against the bottom of the receiver.
As I was fumbling around with dremelling the area around the trigger compartment in the beginning, I had taken down the "shelf" a bit when perhaps it need not have been taken down. This affected the length of my lamp-rod pillar so the pillar now sits a bit above the wood shelf (which I think is a good thing as it is steel to steel all the way from the stainless trigger guard and into the bolt housing base. The base of the rod is flush with the trigger guard. My rod ended up being 2.5 cm.
Front Action
I left in the plastic "semi pillar" that came with the Boyd's stock rather than drill it out. I cut a length of rod to sit on the top of this plastic piece - 5mm - and the top of the rod is flush with wood stock (perhaps just a smidge above) so now there is - from the bottom: action bolt head to plastic, to steel rod, to steel of receiver bottom. The front hole is just big enough for the lamp rod and a bit of room for bedding. Fitting into the recoil lug seems fine. If this rod is high, the action will not sit properly in the recoil lug. The original action bolt works fine for the front.
When all was put together and tightened more than just firmly - everything functioned as it should. I Un-did everything and installed the action back on the stock and low and behold everything functioned just fine. The tang safety was very positive both ways and no way that pressing down on it was enough to drop the firing pin. Initially I had dremelled wood around the tang area and did not have to take any more off. I don't know if I would have had to take some wood, but probably so. At least I didn't take off to much as when the safety is in the safe position it looks bang on.
What's left.
Floating the barrel. There are a couple places of about 2" each where the barrel is rubbing on the stock. This will be the easy part of the fix with dowel/sandpaper. Once this is done, it will be range ready.
Hopefully any/all of this might help someone starting from scratch as I have done with the help of others in the Forum. Thanks for the help.
The extra work will pay off. Yep this is a great community of folks!
Good work. I've also had that problem with what I attributed to the rear of the trigger touching the wood surrounding the rear trigger guard screw. It seems like it was worse with the Timney trigger, but it may have popped up with the factory trigger.
The axial load I calculated using Force = Torque/(Coefficient of friction * Diameter) and then solved for the yield strength of brass I found. However, I used tensile strength when I should have used compressive strength, which is probably closer to 50,000psi for a permanent 0.1% deformation. And good point about the changing contact patch during elastic deformation. I had not considered that previously but suspect you are right.Quote:
Originally Posted by Newsshooter
6 millimeter is not right, screw thread is 1/4" 28, be careful, there is a good chance the threads in the receiver can be ruined with 6MM screws.
Ok question. I know the trigger guard will hold the rear of the action when I tighten the bolt. But what about the front? A washer will just keep the bolt head from sinking in the lamp rod and not keep the front of the action secured......
Proper torque should be adequate. No washer needed. In fact I wouldn't use a washer.
So with no washer the only thing holding the front of the action and pillar is the epoxy??
It is very strong. The washer would be a pita and could cause issues itself.
Ok thank you......So with a 1/2" lamp rod I should drill it out to a 3/8" hole???
3/8 rod...1/2" hole?
A tip I got on the rimfire central forum is to take a small dremel cutter and cut a circular notch in the middle of the hole drilled out for the pillar. Gives the epoxy a nice secure hold.
Lol. Yeah sorry, I was at work and in a hurry. The lamp rod I have is 3/8.....Quote:
Originally Posted by sixonetonoffun
Thanks again Six. I managed to find some 1/4" x 28 bolts at a local hardware - $.40 ea - and have removed the 6M bolt. Indeed, the 1/4" inch one is a nice tight fit. Didn't shoot it with the 6M bolt in and went very carefully so luckily, I didn't damage the threads of the receiver or the trigger assembly.
With the pillar and the bolt being sized, the action is now functioning 100%. I made very sure the top of the bolt was not intruding into the bottom of the bolt housing but catching enough thread so the action bolt can be tightened down very firmly.
This happened to me.. At the very rear of the stock on the inside where the the trigger guard screw protrudes a tiny bit of material was sticking up and contacting the trigger adjustment spring. Two seconds with a chisel took care of itQuote:
Originally Posted by 22BVGord