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Robbie

Mossberg 930 JM Loading Port

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Here's my JM 930 after a little effort to open things up, yea I know I need to smooth things out a bit but it does load easier now than before. Thanks Mark for the nice pics and advice to see the follower showing, that makes a BIG difference.

IMG_0069.jpg

IMG_0064.jpg

I'd like to see some shots of your forearm shaved down. I want to trim my JM fore arm before I go nuts on the port. I'm a new guy so I don't yet know what will be best for me but practicing twins loading my forearm gets in the way a bit. This all sounds really funny if I weren't talking about shotguns...

Has anyone else trimmed down their forearm?

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Here's my JM 930 after a little effort to open things up, yea I know I need to smooth things out a bit but it does load easier now than before. Thanks Mark for the nice pics and advice to see the follower showing, that makes a BIG difference.

IMG_0069.jpg

IMG_0064.jpg

I'd like to see some shots of your forearm shaved down. I want to trim my JM fore arm before I go nuts on the port. I'm a new guy so I don't yet know what will be best for me but practicing twins loading my forearm gets in the way a bit. This all sounds really funny if I weren't talking about shotguns...

Has anyone else trimmed down their forearm? What's needed? What's excessive? What did you use, dremel, sandpaper?

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In message #25 I posted a couple pictures, here's another view.

I just removed the foregrip and slowly worked it down with a table mounted belt sander. For me the ribs on both sides felt odd so I worked them out as well as tappering the bottom.

I smoothed it out by hand w/400 grit to get rid of the scratch marks.

IMG_0092_zps02f566c8.jpg

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I'll have to go to town with with the dremel it is only plastic after all.

Personally, I'd recommend buying a rasps (very course type file) .http://www.instructables.com/id/Introduction-to-Files-and-Rasps/

That way you could get a nice flat and even taper away from the port. Then finish off with various grades of sand paper on a sanding block or wrapped on a piece of wood.

Just my .02

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I'll have to go to town with with the dremel it is only plastic after all.

Personally, I'd recommend buying a rasps (very course type file) .http://www.instructables.com/id/Introduction-to-Files-and-Rasps/

That way you could get a nice flat and even taper away from the port. Then finish off with various grades of sand paper on a sanding block or wrapped on a piece of wood.

Just my .02

Good call. I think a goof file would work as well.

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Dukduk,

Looks pretty good. For me and my hands I felt the thick bump on the sides so I tapered them down. Your hands will let you know if you need to work it down. It's plenty thick on the sides and a good course file can get it down and even, then smooth out w/400 grit.

I'm glad you have your JM back and have a Happy New Year!

crums_zps5634cc48.jpg

Edited by LikesToShoot

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dukduk   

thanks for all you guys' help with the pics! happy new year as well.

it's going to guncat for the xs rear sight next, hopefully back before the club matches start back up (pending ammo availability). my poi was high 18" and left 12" about @ ~50yds. hopefully there's enough windage adjustment so I would only have to figure out poa for elevation.

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bmiller   

Here is the one PT did based on what James and I had previously done. Notice that a lot of effort was put into making the transition out of the loading port smooth so that the "pet" motion can be used. Not the best angle for it, but look at the thickness of the black on the upper edge between the port mod and the side. Notice the angle. It is smoother and faster this way.

FNSLPbyPT.jpg

Could you post a picture from the side view? Thank you

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05202E07-4BF6-49EE-8800-0195CF0FD6E1-1362-000000E9079C3C67.jpg

3FEA3B08-46F5-4DD5-9444-AA3F6D230367-1362-000000E8FF4209D1.jpg

files ands sandpaper. might try to get more clearance like likes2shoot

Looking thinner. Cool! :cheers:

I finally sent my lifter out to Jeff.

I was hoping to save the beans for other goodies but the loading just didn't feel right so now it's a little wait time before I can get practice in.

Local GS had Fed. shells for $57.50 a case OTD so I started collecting a little stash for the up coming season. Also, the Dillon has been getting a work out as well as the tumbler. :D

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JesseCJC   

Looks really good dukduk. I am going to send mine off to get it opened up proper as soon as I can. I started shaping up my forend as well but with it being the wood version I am not sure how that will pan out. Been looking for a synthetic forend just in case but getting through to mossberg is next to impossible in these times.

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JesseM   

Man I wasn't even thinking of having my port opened up any but looking at all these pics is making me reconsider.

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MarkCO   

Proper opening of the loading port takes of about 20% of the time and reduces the fumble factor for TWinS to essentially zero.

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I received my lifter back from C-Rums today, exactly two weeks like Jeff had estimated.

After installing it I feel a need to open up the port a little more on the forward corners like dukduk has.

Now the practice can begin.

IMG_0096_zpsac3ed23e.jpg

Edited by LikesToShoot

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If anyone is interested in trying this modification at home, I documented my process as a tutorial. You can see it below. Total time spent was about 2 hours from strip down to reassembly.

MossbergLoadingPort.JPG

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