Rem 40X Rimfire Actions

[rayjay]

One of the differences in the machining of the rimfire receiver is that the centerfire locking lug abutments are moved towards the rear.

 

[snert]

I have used several Kiff bolts and they are good to go. My new to me 40X rimfire has a Kiff bolt and it is quality. Dan Armstrong, www.accu-tig.com, has it for a new bolt handle. Kerry Stottlemyer built me custom scope bases for it. Designed them in CAD and CNC'd them. He sent photos this afternoon. He just needs to polish them.
Butch

Butch.
Will the one piece scope bases for the Rem 700 work on a 40X rimfire receiver with the 700 foot print? I have an EGW for my 700 SA sitting around and I thought I'd use that.

In early 70's Remington changed the bridge height on rear which is when the letter prefix started on the 700 recievers. The older non prefix and 40-X/XB use same bases. Change was only .017 but 'might' affect how bases made after that change will fit on the earlier 700's and 40-X/XB recievers. Easiest way to check is set base on and tighten front 2 screws. Then check and see if base raised up off of rear bridge. If there is a gap you will either have to shim or bed to fit. Without doing so will cant base to the rear and rob you of elevation.

I have a later 79 XR and using 2pc Leupold bases had to shim .030 so scope would set flat in front and rear rings. Tried 3 different scopes before shimming and none would reach 50yds before bottoming out. Not a real concern with 1pc but with 2pc bases it would be possible to tweak, bend, distort or damage a scope tube.

Contrary to the above now, I used new Leupold bases on a '61 40-X reciever recently and everything lined up great. Guess it depends on machining tolerances and polishing reciever combined with variances in allowed tolerances on bases. Could go in your favor or in rare cases against.

Just a heads up to check so you aren't scratching the noggin later wondering why you have so little elevation adjustment. 1/8 minute clicks makes it worse yet.

Respectfully,
Dennis

WOW! Thank you for that info...now I know why my 700's and my 40XB are different when it comes to bases!!! I needed that info before I tweaked my scope! Again, thanks

Snert