LMT MRP 300BLK info

**ASH556** · 02-17-11, 08:21

IMO, The MRP is the perfect platform to run a 300 blk with. Especially if you're running the SDN6 Silencer. Only 2 bolts and you've gone from say a 556 Recce with an ACOG to a 300blk w/220 subsonics in an MP5-SD size pkg and sound signature. The same can will work for both as well, and the SDN6 has a very similar sound signature to the M42K, which is arguably the best 556 can on the market. I can't wait for LMT to release these uppers! I may just buy a 10.5" 556 upper and then the 300blk barrel when it comes out. How long is the CQB MRP Rail? How about the std MRP rail? How do the barrels fit in them (like how much sticks out on a 10.5", 12.5", 16", etc)?

**khc3** · 02-17-11, 09:57

MRP CQB is approx. a 9" rail.

MRP rail is approx 12".

They correspond to a mid-length and riffle length rail, respectively.

**Anchor Zero Six** · 02-17-11, 10:04

Sorry if I missed it somwhere but are there going to be 300blk specific supressors available? Seems a 308 can would be overkill in regards to size/volume. I'm sure the current cans are very effective but if size is a concern I would think it could be scaled dow.

Just wondering...

**JasonM** · 02-17-11, 12:00

Originally Posted by Anchor Zero Six

Sorry if I missed it somwhere but are there going to be 300blk specific supressors available? Seems a 308 can would be overkill in regards to size/volume. I'm sure the current cans are very effective but if size is a concern I would think it could be scaled dow.

Just wondering...

We tested a bunch of configs including taking one of our M4-2000s and boring it out to 30 cal... it was pretty good, but the difference of then going to a slightly longer and heavier 30 cal can was pretty amazing.

As close to a purpose-built 300 BLK can you can get is our 762-SDN-6 which gets sound (with subsonic ammo) below the sound levels of an MP5-SD.

Versus the 5.56-sized bored-out can, the performance of the 'N-6 is WELL worth the extra 1.7oz and 1".

Although some of the large, heavy 30 cal cans out there are certainly overkill for the round.

**Anchor Zero Six** · 02-17-11, 13:58

Originally Posted by JasonAAC

As close to a purpose-built 300 BLK can you can get is our 762-SDN-6 which gets sound (with subsonic ammo) below the sound levels of an MP5-SD

Now thats an impressive statement!

**JasonM** · 02-17-11, 14:20

Originally Posted by Anchor Zero Six

Now thats an impressive statement!

impressive fact.

The overall SPL of 126 dB with 300 AAC BLACKOUT subsonic ammo is 4 dB quieter than the HK MP5-SD.*

*MP5-SD tested with Winchester 9mm ammo at 900 fps. Small Arms Review, April 2001, Vol 4 No. 7.

300 BLK tested using a 9" AAC 300 BLK PDW AR Upper.

**DHart** · 02-20-11, 05:41

300 BLK is really looking like a great caliber for an AR CQB/Home Defense rifle. I have been thinking I would go 6.8, but 300 BLK may easily win me over. This is an exciting development for the AR platform.

**Frank Castle** · 02-21-11, 08:13

Originally Posted by DHart

300 BLK is really looking like a great caliber for an AR CQB/Home Defense rifle. I have been thinking I would go 6.8, but 300 BLK may easily win me over. This is an exciting development for the AR platform.

The beauty of the MRP platform- you don't have to limit yourself to a single caliber.