Finally got to pattern the mossberg - Now have a few questions

[Extremesolo]

I was able to get out yesterday with my new Mossberg 500C, 21" barrel and a pure gold .555 choke.  Temperature was right around 60 with a slight breeze.  I had federal HW #&, Hevi #7 and Hevi #6 to shoot through it.  All shots were at 40 yards in a 10" circle.  Hevi 7's gave me the best pattern with 122, Federal HW #7 gave me 86, and Hevi #6's gave me 81.  I would really like to use the federals because I think they are a little better load than the hevi-13 and I have 3 more boxes of the federals.  Nothing against the hevi-13 and they are good as well but the heavier federals seem to hit harder.  I am thinking of trying a different choke in this Mossberg like the high density undertaker .582.  I have seen where some other guys on here have excellent results with the .582 undertaker.  Any ideas why the HW did not pattern well but the hevi-13 did fairly well through my current choke?  Possibly the wad or different amount of payload?  Any help on the choke recommendation or thoughts on the pattern discrepancies are welcomed.

[wmd]

I had a similar experience with a Reminton 1187 20 ga.  I started with the SSX .550 which is the go-to choke for the 870 20 and HW 7s.  I couldn't break 100 with the Federal 7s and got 110-130 with Hevi 7s and Nitros.  I bought an Indian Creek and didin't see any improvement.  I got slightly better HW 7 numbers with a RSF, but tried a Carlson's .575 and it is a shooter now.

HW 7 = 155
HW 6 = 120
Nitro MW (4x6)MW x 7HS= 160
Nitro 4x5x7 = 150

I would definitely try a more open choke and see what you get; you might be surprised.

[Dallen92]

I am pretty sure I have the same gun and mine does well with the .575 undertaker.  It is not the high density one. It will put up around 170 at 40 with fed hwt 7.  It does really well from far out to close in.  I was able to call up a bird for a youth that came in much closer than I wanted with it and he connected on him at 7 steps. I was worried it would be too tight but it got the job done perfectly.

[BigStrutter]

Same here. I use both the .575 and the .582 in my 500 and they shoot really well. Sometimes you have to open the choke up little to get a better pattern.
Try the .575 in the Undertaker or Carlson's as wmd suggested. Good luck!

[Extremesolo]

I am going to buy an undertaker to try. Do you think I would be better off with a .575 or a .582. Will I notice much difference between the two with hw 7s, Hevi 7s and Hevi 6s?

[surehuntsalot]

get the .575

[jdub2041]

Call sumtoy he should be able to get u fixed up

[learn2hide]

even though I can't speak to it exactly as I'm a 12 ga shooter...the Fed HW 7's patterned 25% less than Hevi 13 6's for me...but it's also 2.25 oz load vs 1 7/8oz load of heavier shot...so there definitely less pellets to start with but I've heard they hit like a    Good luck with your choice and season