MDT poly mag issue in KRG W3/Ultimatum Deadline R700 clone action

[goatboy]

Calling on the MDT, KRG and or Ultimatum experts.

I need some advice. I've just rebarrelled an Ultimatum Deadline in KRG W3 chassis from 6.5CM to a 223.

The MDT poly AICS mags that I bought wont feed, the rounds are just pushed by the bolt into the breech and not presenting into the feed ramp. Its like the round are either not high enough or coming into battery at an upward angle.The magazine locks into place and the mag release functions.

Before I just trying different magazines, does anyone have advice on how to address this?

There is not a lot of play in the forend and I did find that the trigger guard screw wasn't tight. There wasn't much fore-aft play, just up and down or in/out along the axis of the trigger guard screw (bolt). When everything is loose, it would load a round but I could neither understand the issue nor duplicate it when things are tightened.

I believe its a Gen 5 Whiskey 3 if it makes any difference.

 

[jcmullis2]

You probably need the mag with the plate. Krg mentions that feed problem if you don’t use the mags with the plate. Some people take a Dremel to their action but I wouldn’t do an action of mine like that but some do. If your mag has the plate then I don’t know why it would do that.

 

[never_summer]

While not an ultimatum my axiom is a 3 lug and somewhat similar. In my Krg chassis even with the forend moved forward the bolts would bring it back and cause my mag to be too snug. The mdt ribs on the bottom were causing mine to bind and I filed the front one flush. Now the mag has play and it loads super smooth. Might not be the same with yours but if you mod it and don’t want it... I can use another
edit: you can probably disregard me, I forgot there is an aftermarket barrier stop on the front of my magwell hanging down. Too much working in quarantine

 

[jcmullis2]

My whiskey 3 has a defiance action with a 6.5 creed in it and I have to use the mags with a plate. I just re read what Krg said and it doesn’t apply to 223 mags. If you don’t get any help from the other guys I’d message or call krg and see what they say. They’re pretty good about answering theIr emails and you’re likely to hear back by tomorrow. Sorry about your little snag and hopefully you get it sorted out real soon.

 

[308Gunner]

I could not get them to work for me but AI mags are butter

 

[goatboy]

Ok. Working the feed lips of the MDT, shaving them down with a sharp pocket knife, I got a single round to load but since the follower is more or less flat, when a set of rounds are loaded in the magazine, the nose of the top round points down and doesn’t engage the feed ramp. Jam.

I caught up with KRG and they suggested the Accurate Mags. Two of them arrived yesterday and 5 rounds cycled flawlessly through them. I’ll get out for a range test tomorrow but I’m feeling gtg.