Results 1 to 9 of 9

Thread: new chasis for my Ruger American 300AAC

  1. #1

    new chasis for my Ruger American 300AAC

    I ordered one of these Modular Design Technology "LLS" aluminum chassis for my Ruger American 300 AAC. I have found that I enjoy that rifle for target shooting as much as anything so I decided to upscale it. It takes their AICS-style 10 round mags and all the AR goodies with regards to buttstock and grip. I still have the Adjustable stock from my Ruger RPR I will install on mine, along with the RPR's original pistol grip. I have an Atlas bipod for the front end.

    Dealing with the manufacturer was one of the most pleasant shopping experiences I've had in a while. It ships Tueday morning and I'm told it will arrive by Friday. I will have it at the range an hour later! ~Muir

  2. #2
    Well. That was disappointing.
    The chassis arrived and went together easily, but it would not, and as far as I can tell, will never feed 300AAC Blackout without a major magazine redesign. Like the Ruger, it was assumed that a .223 magazine would work for the 300BLK. It just isn't so in some magazine feed weapons and the Ruger American is one of them: The shorter 300BLK cartridge comes out of the feed lips before it begins to enter the chamber. It works in AR-15 because the magazine has feed guides on the front end that keep pressure on, and guides, the cartridge as it transitions into the chamber. If they produce a new magazine that leaves the cartridge angled upward in front, with longer feed lips and a guide ramp, it would probably work. Unfortunately, it would probably behoove them to simply state that it isn't suitable for the 300AAC.

    Not a huge loss on my end. I had a Ruger American Ranch in .223 so I simply dropped the the barreled receiver into the MDT chassis. Feeds fine. Looks good. ~Muir

  3. #3
    Interesting, Any Photos Muir ....

  4. #4
    Quote Originally Posted by GOMX View Post
    Interesting, Any Photos Muir ....
    I'll take a couple tomorrow at the range. This rifle has turned into a project....

    The magazines that fed 'fine' actually stopped functioning as I got down to 3 rounds left in the magazine when I put them to field tests. The way I used the platform for prairiedogging during the Soap Creek Prairiedog Association meet was to load three FMJ and top the stack with my varmint loads. When I got down to the FMJ I reloaded the mag. It worked but was a minor pain in the arse.

    MDT was good taking the mags back and as it happened, my buddy tossed me the 5 round AICS mag from his 20 Practical and it worked flawlessly. The magazine was made by "Accurate Mag" in Connecticut. Not Cheap: $64 for a 5 rounder and $70 for a 10 round unit. I ordered a five and two tens and waited. Meanwhile, I sent the MDT mags back. They were very apologetic and somewhat puzzled that I had a failure in .223. I think it is due to the 'feed lug' of the three lugs on the bolt pushing the shorter column of cartridges nose down. They are sending me a couple of magazines to gunsmith into functioning and, as a way of apology, offered me a good deal on a folding stock adapter for my LSS chassis. That's plenty fair enough. The chassis was one of the most comfortable platforms for varminting I've used. Suited my shooting arrangement very well. The Accurate Mag magazines arrived yesterday. I installed a taller magazine catch (MDT thoughtfully included four different lengths to accommodate different magazine makes) and the mags are tight and feed 223 like a hot knife through butter. I am thoroughly pleased. I ordered two more mags last night and another 1000 Nosler 55 grain Ballistic tip Boat Tails. There are still a LOT of prairiedogs out!~Muir

  5. #5
    I had similar problems with my Tikka T3 in 260Rem using their TAC-21 chassis, the magazine would about 1.5 - 2mm allowing the bolt to go over the top of the round without feeding it.

    They are well aware of mag latch length problem but were very helpful, eventually sent me 3 different lengths to try.

    The MDT 10 shot "308" style mag has well known problems, you can't use more than 9 rounds in it as it's just too small and won't fit/feed properly when stuffed with 10.

    I bought a genuine AI mag and that fed fine but was very noisy and a pain to load so I sold it on. I now just use 5 at a time in the MDT. I was hoping the new Magpul 10 round polymer Aics mags would work but apparently it also has problems in MDT chassis with the feed lips needing modified.
    Last edited by phaedra; 02-07-2016 at 09:01.
    There's room for all Gods creatures ........... right next to the mash and gravy

  6. #6
    I guess it's a common thing that these mags need tinkering and filing upon. I can't understand why the chassis makers just don't offer the chassis in a configuration that takes Mag Pul LR and AR 15 magazines and be done with it. I spent $400 on magazines for this chassis which is not a good selling point for equipping a $358 rifle. You've had your issues, too, it seems. Looking practical and tactical, and not acting it, is a lot like having a Porsche with a VW engine. It just doesn't feel right.~Muir

  7. #7
    Quote Originally Posted by Muir View Post
    I guess it's a common thing that these mags need tinkering and filing upon. I can't understand why the chassis makers just don't offer the chassis in a configuration that takes Mag Pul LR and AR 15 magazines and be done with it. I spent $400 on magazines for this chassis which is not a good selling point for equipping a $358 rifle. You've had your issues, too, it seems. Looking practical and tactical, and not acting it, is a lot like having a Porsche with a VW engine. It just doesn't feel right.~Muir
    It is not the chassis (or bottom metal) that are able to make a rifle accept AR-15 magazines. The action itself would need to be modified to make this work, which is why AICS magazines are a standard for bolt action rifles. With the exception of the Mossberg MVP, who's mechanism to use AR magazines is patented.

  8. #8
    As for the .300 BLK issue, we are looking into this further!

  9. #9
    Quote Originally Posted by MDTcorp View Post
    It is not the chassis (or bottom metal) that are able to make a rifle accept AR-15 magazines. The action itself would need to be modified to make this work, which is why AICS magazines are a standard for bolt action rifles. With the exception of the Mossberg MVP, who's mechanism to use AR magazines is patented.
    I remembered this after I posted. Sorry. Too little sleep! This is explained on your web-site in detail. The Ruger seems to be a rough one to make feed. As I mentioned, even the factory Ruger .223 mags won't feed 300 AAC. I hope you get the 300 issue fixed. ~Muir

Similar Threads

  1. Ruger American Predator
    By Muir in forum Rifles & Calibres
    Replies: 8
    Last Post: 29-08-2017, 17:09
  2. For Sale Ruger American Rimfire .22L/R
    By multiman in forum Firearms
    Replies: 6
    Last Post: 11-06-2015, 22:42
  3. Ruger american
    By Renico in forum Rifles & Calibres
    Replies: 9
    Last Post: 07-06-2014, 22:16
  4. Ruger American Bolt
    By paultap in forum Rifles & Calibres
    Replies: 7
    Last Post: 29-04-2014, 00:05
  5. *SOLD* Ruger American 308 synthetic (new)
    By paultap in forum Firearms
    Replies: 12
    Last Post: 31-03-2014, 19:07

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •