Boyd Allen
Active member
Al,
You are welcome. It seem that I have been caught using a rhetorical question. So, do you disagree?
Boyd
You are welcome. It seem that I have been caught using a rhetorical question. So, do you disagree?
Boyd
It is interesting that Savage changed the diameter of their barrel tenon just slightly after they had issues with the smaller tenon and the WSM family of cartridges.
There is excellent reading in "Rifle Accuracy Facts" about the relationship of barrel threads to accuracy and strength and also about the recoil lug being rigid.
I've made a few switch barrel Remington rifles and XP100 pistols. I bevel a small groove into an aftermarket, thicker recoil lug and a small bevel on the bottom of the action. TIG welded and filed flat, you can't even see it and it doesn't upset the bedding. The welding is simply to hold the recoil lug in place. It does not have any stress at the weld. The barrel needs to be installed and tourqued to final spec before welding is performed to be sure the recoil lug is in maximum contact with the action.
I've had a locating pin break on at least one action where I drilled and pinned the recoil lug to the action. I have no idea why..................??
There is excellent reading in "Rifle Accuracy Facts" about the relationship of barrel threads to accuracy and strength and also about the recoil lug being rigid.
I've made a few switch barrel Remington rifles and XP100 pistols. I bevel a small groove into an aftermarket, thicker recoil lug and a small bevel on the bottom of the action. TIG welded and filed flat, you can't even see it and it doesn't upset the bedding. The welding is simply to hold the recoil lug in place. It does not have any stress at the weld. The barrel needs to be installed and tourqued to final spec before welding is performed to be sure the recoil lug is in maximum contact with the action.
I've had a locating pin break on at least one action where I drilled and pinned the recoil lug to the action. I have no idea why..................??
CYanchycki
Club Coordinator
Okay so there are a few people who think this is a BAD idea.
I have to be honest here. I am going to be the guy sitting behind this thing and pulling the trigger. I would really like more opinions on this.
Has ANYONE actually done this and felt confident that things would be okay????? You can reply here or send me personal e-mails at cyanchyc@mymts.net.
I am one who loads to get the maximum performance out of a cartridge. What that means if I could stuff 30grs into a 223 case and get decent accuracy I would. Same goes for the 6BR. The feeling I am geting is this is a bad combination going this route...............
Like I said I am also prepared to sacrifice this action to see how it would handle the pressures of repeated hot loads....
Calvin
I have to be honest here. I am going to be the guy sitting behind this thing and pulling the trigger. I would really like more opinions on this.
Has ANYONE actually done this and felt confident that things would be okay????? You can reply here or send me personal e-mails at cyanchyc@mymts.net.
I am one who loads to get the maximum performance out of a cartridge. What that means if I could stuff 30grs into a 223 case and get decent accuracy I would. Same goes for the 6BR. The feeling I am geting is this is a bad combination going this route...............
Like I said I am also prepared to sacrifice this action to see how it would handle the pressures of repeated hot loads....
Calvin
Before I would sacrifice an action I would sacrifice one of the sleeves. Cut it lengthwise and be able to physically see and measure what kind of wall thickness you have left. Imo the whole 'switch barrel' scenario is over hyped. Ime it worked better to have whole rifles in the safe zeroed and ready to go.
CYanchycki
Club Coordinator
Another clarification, it is not something that the barrels will be constantly switched back and forth. It MAY on OCCASION happen.
Boyd Allen
Active member
You might want to review this thread, especially the first post, and #11. http://benchrest.com/showthread.php?56991-The-significance-of-tenon-diameter&highlight=
D
Dennis Sorensen
Guest
Slight change of plans due to the concerns expressed in this thread.
I will continue with this alteration and test high pressure 6mm BR loads and monitor the headspace. If the headspace doesn't change, the bushing is holding.
However I am keeping this action and replacing it to Calvin with a trued .223 action using his new bolt assembly and with a Holland lug welded in place and his 223 barrel fitted. I know he will never have a problem with that set up and I will keep testing the conversion.
I will update this thread when applicable.
I will continue with this alteration and test high pressure 6mm BR loads and monitor the headspace. If the headspace doesn't change, the bushing is holding.
However I am keeping this action and replacing it to Calvin with a trued .223 action using his new bolt assembly and with a Holland lug welded in place and his 223 barrel fitted. I know he will never have a problem with that set up and I will keep testing the conversion.
I will update this thread when applicable.
I'm not at all worried about the headspace. My issue isn't with the "safety" of the thing, it's with the skinny tenon. The tenon resists expansion. IMO ONLY the tenon diameter has an effect on expansion. I don't think it'll run hot well.
And I predict it'll shoot 3's at best and it'll split clusters, because you're trying to lock not one but two threaded joint buttments in a very violent environment. (Again, not 'safety' just violent forces at work. Like inside a combustion engine)
al
And I predict it'll shoot 3's at best and it'll split clusters, because you're trying to lock not one but two threaded joint buttments in a very violent environment. (Again, not 'safety' just violent forces at work. Like inside a combustion engine)
al
CYanchycki
Club Coordinator
To those who have given there input and thoughts, THANKS.
I LEARNED a LOT reading this thread. What finally made it all click was reading the link that Boyd put up in regards to Gene's findings. Things were a little unclear till then but not any more.
I began to realize that I would not feel comfortable behind the rifle knowing in the back of my mind that there could be possible issues. Testing and experimenting is up to the guys who have the ability to fix the problem if one arises. I know what a lathe looks like and that is it. My daughter taught me what the headstock and tailstock are thanks in parcel to shop class.
Al mentions the violent forces, well I like to have those forces on the edge. If it shoots well at the top end that is what I would like. I am not one to use the next cartridge up in size and load it down to achieve the same effect. Anyhow.....................I still look forward to having a rifle in my hands.
Calvin
I LEARNED a LOT reading this thread. What finally made it all click was reading the link that Boyd put up in regards to Gene's findings. Things were a little unclear till then but not any more.
I began to realize that I would not feel comfortable behind the rifle knowing in the back of my mind that there could be possible issues. Testing and experimenting is up to the guys who have the ability to fix the problem if one arises. I know what a lathe looks like and that is it. My daughter taught me what the headstock and tailstock are thanks in parcel to shop class.
Al mentions the violent forces, well I like to have those forces on the edge. If it shoots well at the top end that is what I would like. I am not one to use the next cartridge up in size and load it down to achieve the same effect. Anyhow.....................I still look forward to having a rifle in my hands.
Calvin
D
Dennis Sorensen
Guest
Browning A Bolt's use a tenon that size in Magnum calibers and don't have a problem with factory loads or 'normal' hand-loads. This isn't a Benchrest rifle trying to wring out more than everything with what might be excessive loads. Monitoring the headspace should give an indication if the bushing does fail in any way. I agree though - the larger the tenon the better it handles hard extraction due to excessive pressure.
it'll shoot like an A'BoltWell, predicting is fun. Sort of like gambling. Those of us who don't bet on card playing, or the ponies or sports contests, have to get our gambling in somehow.
With a worked-up load, I'll bet the .223 shoots in the 3s. Less sure about the 6 BR, the high 2s wouldn't surprise me, but I think it too will shoot in the 3s. Not benchrest accuracy, but OK for hunting.
We shall see.
With a worked-up load, I'll bet the .223 shoots in the 3s. Less sure about the 6 BR, the high 2s wouldn't surprise me, but I think it too will shoot in the 3s. Not benchrest accuracy, but OK for hunting.
We shall see.
D
Dennis Sorensen
Guest
I tend to agree. It was never intended to be a Benchrest competition rifle - just an accurate varmint rifle. With a new barrel I think those accuracy levels are realistic. (high .2's - low .3's)
The magnum A Bolt hunting rifles I have re-barrelled have usually shot from 1/2 to 3/4 inch. No extraction problems with maximum book loads and the skinny barrel tenon. These aren't competition Bench rifles.
D
Dennis Sorensen
Guest
I stuck this in a stock and without a scope I fired 6 fairly high pressure loads just to see if anything would change... they are not hot enough yet... only 2.5 grains over book maximum for H322 and an 87 grain bullet... and extraction is not hard.
Headspace did not change, I'll update this after the next trip to the range...
Well I have now shot a few loads 5 grains over book max and the bolt lift is hard and the primers are starting to crater and the brass is getting shiny around the primer pocket on extraction and the extractor groove has expanded almost a thousands of an inch in diameter.
The headspace has not changed.
Personally I don't work loads this hot for a constant fodder for hunting or varmint shooting...
I seriously doubt there are any safety issues with this project and .308 size cartridges. I am going to continue testing when I have more time. I might have to put a new barrel on to test for accuracy... although this barrel has been set back and has a short throat, it also has 2500 rounds through it... but I'll give it a try first. I have a few good barrels threaded for Sako actions that I can re thread and fit to this bushing...
Headspace did not change, I'll update this after the next trip to the range...
Well I have now shot a few loads 5 grains over book max and the bolt lift is hard and the primers are starting to crater and the brass is getting shiny around the primer pocket on extraction and the extractor groove has expanded almost a thousands of an inch in diameter.
The headspace has not changed.
Personally I don't work loads this hot for a constant fodder for hunting or varmint shooting...
I seriously doubt there are any safety issues with this project and .308 size cartridges. I am going to continue testing when I have more time. I might have to put a new barrel on to test for accuracy... although this barrel has been set back and has a short throat, it also has 2500 rounds through it... but I'll give it a try first. I have a few good barrels threaded for Sako actions that I can re thread and fit to this bushing...
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