Nelson .22 conversion accuracy

I'm building my home version of the Nelson conversion, I do have the Nelson still new , never fired. I made a one piece barrel and will insert a sleeve bought from Brownells. My thoughts were to get the barrel correct and function reliably then us the dimension to make a one piece barrel from a High end barrel blank.
 I'm wondering what group size other are getting with the Nelson Barrel?
 Nelson barrel will not fit my conversion, I've made changes in the design so I want to know how accurate the Nelson is to compare to what I built and if using a high end barrel will make it better.

Frank,
They are hit or miss. They’re not indicating off the bore when crowning the barrels. A so so barrel is 1.5” with cci sv. Same barrel recrowned 0.75”. Otherwise typically about 0.75” with cci sv.
Jon

So what your saying Jon is the barrel was not turned concentric with the bore. And they crowned using the OD of the barrel and best with few exceptions with a Nelson is a 1.5" group or greater with a flyer. Not very good for a .22 pistol. Re-crowning will bring it down to .75", not too bad. The homemade IZH-35 copy using a Lilja barrel Floyd Aikman sent me would group .625" at 50 yards

Jon Eulette wrote:Frank,
They are hit or miss. They’re not indicating off the bore when crowning the barrels. A so so barrel is 1.5” with cci sv. Same barrel recrowned 0.75”. Otherwise typically about 0.75” with cci sv.
Jon

Jon, is this also true of the original (non-lock back) Marvel Unit 1 conversions?

RodJ wrote:

Jon Eulette wrote:Frank,
They are hit or miss. They’re not indicating off the bore when crowning the barrels. A so so barrel is 1.5” with cci sv. Same barrel recrowned 0.75”. Otherwise typically about 0.75” with cci sv.
Jon

Jon, is this also true of the original (non-lock back) Marvel Unit 1 conversions?

Not Jon but I bought mine at Perry one year from Bob Marvel and here is a picture of the test target. I think Bob was using micro groove barrels when he made this one in around 2005. He also had one of his custom 1911's on display and wish I could have bought it also.

Early Marvels crowns/muzzles were cut with a hand operated piloted cutter. Later they lathe cut them. 
Fortunately they have always tested the barrel accuracy, so you have an idea how they’re going to shoot. I’ve had several Marvels shoot consistently 0.6” or better from RR.
Jon

Thanks! I think mine is roughly 2001-5 era. 0.9” test target. Was curious. Can’t find a serial number/ date list. Hmm

I'm interested buying a Nelson Barrel assembly no matter how bad the barrel is. The barrel will be removed and another made or just the mounting assembly without the barrel.

Mine came with a test target of .79" from FCW.  Got it last year.

How are the barrels mounted in the block? Threaded or press fit?

LH thread Scott.
Jon

HERE ARE THE TEST BUTTONS FOR MY MARVELS. REALLY SMALL GROUPS USING THE LAPUA SIGNUM AMMUNITION. I STILL HAVE 2K OF THE SIGNUM THANK GOODNESS. USING CENTER X ADDED ABOUT 1/8" TO EACH WHEN I RR TESTED THEM.

Froneck wrote:I'm building my home version of the Nelson conversion....

Larry went to a lot of work to make the Nelson kit "dry-fire friendly".  
If you're building your own, you may find that, and other things, that weren't obvious in the original design.