22-245 AI

[scooter]

I have an Ackley 22-250, and using Lapua brass, my case length is short compared to what the case length is supposed to be. My measurement in length with Lapua is 1.878 versus 1.892, as specified by Sierra manual. I had my gunsmith bore scope the barrel and he said there is approximately 1/8 ring of carbon in throat. What can be done to prevent this?

 

[boltfluter]

JB's or Rem Clean is your friend on a tight fitting jag.

Paul

 

[lpreddick]

I have an Ackley 22-250, and using Lapua brass, my case length is short compared to what the case length is supposed to be. My measurement in length with Lapua is 1.878 versus 1.892, as specified by Sierra manual. I had my gunsmith bore scope the barrel and he said there is approximately 1/8 ring of carbon in throat. What can be done to prevent this?

I suspect the "carbon ring" is in the very end of the chamber...short brass and long chamber is asking for thus. This carbon deposit is commonly overlooked as pushing patches will not get it out.. The problem with it is that it hardens as repeated firings bake it. If a longer case is chambered, this ring can slightly crimp the case tip and groups open. Spinning a very stiff brush(iasso and Hoppes make these) with some JB will remove it. Once established it is not easy to remove and if you do remove it you can see a staining in this portion of the chamber.

 

[B23]

I have an Ackley 22-250, and using Lapua brass, my case length is short compared to what the case length is supposed to be. My measurement in length with Lapua is 1.878 versus 1.892, as specified by Sierra manual. I had my gunsmith bore scope the barrel and he said there is approximately 1/8 ring of carbon in throat. What can be done to prevent this?

Whenever you blow the shoulder out the overall length of the case shortens.