Universal multi-caliber conversion for Rem 700 and Savage 10

[1stmarine]

I was reading the thread about the 7.62x39 bolt action carbine and then I realized how long
it has been since I have reloaded and shot that round and that I might convert a barrel I have to use with a new universal system I fabricated.
I have decided to post this project here so others in the same or similar situation might
take advantage of this method.

I have a fair assortment of old barrels in many calibers that I want to use but some belong to several actions I don't even have anymore. Some are seasonal and many wildcats too....sounds familiar?

So I decided to fabricate a bushing to convert action threads to universal threads and a quick barrel swap system in a Remington 700 and Savage 10 bolt action.

The bushing will give me the choice to have a shoulder that will hold the recoil lug in place and it should be strong enough to torque down to 80ft-lb or so. Initially I have decided to avoid the traditional recoil lug for additional strength and instead I cut a slot on the bushing to go with a sako style lug enbedded in the stock. I am machining this next.

This stub approach has two threads in the tenon, one for the bushing's internal threads and another one for the barrel nut that will be the same nut used by the Savage and Remington actions of 1.060x20tpi and 1.055x16tpi respectively.

For other barrels I will make a barrel nut using a standard 30 mm 12 point nut in order to torque down the barrel to 40ft-lb after headspacing. In essence, this is no different than the popular savage system, just reduced to a smaller thread for small caliber and quick swap.

I made a rough test and everything seems to fit pretty well.

Outside threads are 1.055x16" standard on this Version 1.0

Inside threads are M22x1.5

The bushing is flush with the action and it has a cut for the recoil lug.

This test was made with some bar stock in SS I had laying around. Not sure what type
but it is on the hard side.

 

[1stmarine]

I cut a large recess/relief to receive standard threads and this way I will be able
to use standard R700 or Savage small shank barrel nuts.

I cut a short stub to test fit. I have a few Tupperware stocks from factory rifles that I will be using
for the project. My idea is to bed the action and then have a two piece stock so I can remove the
hand-guard w/o removing the entire stock to swap the barrel. For this I will also drill and tap
the bushing with the lug so the entire unit will be stronger and it can be put in a vise w/o putting
stress in the action screws. In other words, it would be locked up in place after bedding. Will also
be stress free bedding.

Now I need to make a sako style lug with a cut to match the slot in the new bushing.
I am going to do this as a one piece recoil lug plate and then anchor that to the
action with bedding compound. I might not need to bed the plate it but if I do, it will be skim
bedding only.