Mossberg Accu-Mag Choke Tube Constrictions ?!?!?

[dust_101]

Ok, bit confused here. I just purchased an earlier model 835 (woodland camo, white dot front bead) for turkey, I used to think I knew about chokes and patterning but this has be confused.

I just went through all the Accu-Mag chokes to see which one may be best for turkey, and that of course will be seen by the pattern board, but can anyone lend some thoughts on this:

Improved cylinder Accu-Mag choke tube
0.765" constriction
For lead, steel & non-toxic loads
Mossberg 95252

Ulti-Full Turkey Accu-Mag choke tube
0.765" constriction
Lead only
Mossberg 95257

Modified Accu-Mag choke tube
0.750" constriction
For lead, steel & non-toxic loads
Mossberg 95253

Full Accu-Mag choke tube
0.730" constriction
For lead, steel & non-toxic loads
Mossberg 95254

X-Full Accu-Mag choke tube
0.715" constriction
For lead, steel & non-toxic loads
Mossberg 95255

Where/How does the "Ulti-Full" choke fall into this? It has the same measured constriction as IC but only takes Lead shot?

 

[chas08]

I'm not real familiar with Mossbergs, but perhaps it is meant to be used with an "Overbored" barrel

 

[Dave McCracken]

The Ulti Full is almost certainly made from a softer alloy, and use with steel shot may cause damage.

You're right about patterning, it's the only way to ensure your shot will do the job.

I'd try the tighter tubes with the load of choice and see what happens at 40 yards. I'm not enthused about longer shots on living things. Stay within your comfort zone.

 

[dust_101]

Well, one thing... the numbers are not correct. I just pulled the choke out of my 835, it is stamped "ULTI FULL" "TURKEY CHOKE" but it mic's at 0.694" which is not what I've seen on the web.

So yes, this looks like a softer metal, lead only (no problem). The 0.694" though looks like a standard FULL measurement from a 12ga. on this chart. It HAS to do with the 835 being overbored to a 10ga with the longer forcing cone.

Regardless this is going on paper right after work. 40yd test as the max effective range.

Just wish these Mossberg chokes made a touch more sense in their naming setup

 

[Dave McCracken]

It's not just Mossberg. Remington has a skeet choke with negative choke, larger than bore diameter. Most makers these days call a skeet choke about 5 POC, tighter than Cylinder and looser than IC.

Remington also jumps from 20 POC with a Modified Remchoke to a Full of 39 POC or so. 25 or 30 POC chokes have lots of utility.

And except for turkey, there's not much use for a 40 POC choke with modern ammo. Patterns with a 30 POC choke may actually be tighter due to less deformation at launch.

So, it's a bit of a crapshoot. Good luck....