The Accurate Reloading Forums
12 gauge choke

This topic can be found at:
https://forums.accuratereloading.com/eve/forums/a/tpc/f/9411043/m/199102246

18 March 2007, 19:06
griff
12 gauge choke
I would like to ream out the choke in my remmy 1100(full) to 1/2 choke, can anyone tell me the diameter for 1/2choke and how far does the choke go down the inside of the barrel?
It currently measures .700" I intend to use a 6 blade adjustable reamer is this the best way?

regards
griff
18 March 2007, 19:37
Westpac
quote:
Originally posted by griff:
I would like to ream out the choke in my remmy 1100(full) to 1/2 choke, can anyone tell me the diameter for 1/2choke and how far does the choke go down the inside of the barrel?
It currently measures .700" I intend to use a 6 blade adjustable reamer is this the best way?

regards
griff


The 12 gauge bore is .729. There are 4 points of constriction on the 12 gauge barrel from full choke to bore. Each point is .010. Therefore:

Full .689
Improved Modified .699
Modified .709
Improved Cylinder .719

And every other odd duck size in between. Big Grin

I don't have one at the moment to measure, but the length from where the taper begins to the muzzle is about 2 inches +/-. The actual part you will be opening, the parallel section of the choke, is about 1 inch +/-.

Clamp the barrel vertically in a padded vise and feed the reamer straight down (with gravity) in very small increments. Use a large tap handle, plenty of cutting oil and keep the pressure "uniform". Keep the adjustments small. Start .002 over choke and increase the diameter at intervals of no more than .002 per pass to avoid trouble.

FWIW, for "Steel shot" use, I open 12 gauge chokes to .705.


_______________________________________________________________________________
This is my rifle, there are many like it but this one is mine. My rifle is my best friend, it is my life.
18 March 2007, 20:41
griff
westpac,
thanks for that. My next question would of been regarding steel shot but have answered that.

many thanks
griff