Just saw that Volquartsen sells a takeoff 5.5" heavy barrel and receiver for a Mk IV, complete with sights but no bolt.

Seems like a terrific deal - I figure the receiver would fit right on with no problems but I was wondering if the bolt would need any kind of fitting at all? My instinct says no, just slide that puppy in and start firing but I wanted to check with the cognescenti here before placing an order.

For those of you on pins and needles waiting for the answer, yes, it does. Just got a very fast reply to my email to Volquartsen.

Me: Re the barreled receiver you offer for the Ruger Mk IV without bolt. To your knowledge does the existing bolt from my Mk IV Standard just slip right in without any fitting?

Volquartsen: Yes it does.

Well, I look forward to seeing pics of the new acquisition and some targets, Jim!

I'll do my best.

Got a Mk IV Standard with the fixed sights and a Volquartsen accurizing kit installed and really like it but was hankering for a new toy with adjustable sights. Have been perusing gunbroker for a Target model which seems to run in the mid $400 range at a minimum - plus Idaho tax plus gunbroker compliance fee, but then stumbled onto these take off barreled actions for $40 + $15 shipping, no tax charged. The ones they offer come off of Ruger 22/45 models 40107 but the receivers are identical, they just pop on and off.

Have one more question in to them about the FFL transfer but once I hear back will most likely get myself a belated Christmas present.

OP,
Replace the magazine safety parts w/ a hammer bushing for function & reliability.

The upper receiver/ is the serialized part of any Ruger MkI,II,III,IV pistol that will require a BATFE 4473 transfer.

22/45 magazine base plates differ from MKII, MKIII,MKIV base plates.