I would be curious If lightening the carrier would screw with cycling other calibers for the ACR. Since I plan on going to Marvin for any and all conversions I'm sure he could adjust for that. I will consider lightening the carrier. The drop in felt recoil appeals to me.
12-14-2013, 04:49 PM
That is pretty awesome. I like the new look to it as well. Very customized. Does Marvin have an idea to the cost of this modification?
12-14-2013, 07:25 PM
Also wondering the price for the mod, how much is the carrier itself too?
A lightened carrier could work better with 300blk
12-14-2013, 08:25 PM
As soon as I can find a Surefire brake to pin on it I'll have a barrel to test that with, but Marvin said before that he can tune his regulator to what I need. But I don't see whay it would be really needed. Each conversion barrel would have it's own gas regulator that would be tuned to that cal. already so if it cycles well with the factory gas system then I dont see why you would need any more tuning than usual.
The factory recoil spring seems more than stiff enough , I'm actually wondering if it can go lighter. The recoil reduction is pretty substantial, it's kind of addictive. Also it does cycle faster so my rate of fire has picked up a little. Before I could shoot fast enough to outrun the gun, but I can't do that anymore, the gun's faster than me.
When Marvin and I discussed the weight reduction, there is most certainly a threshold where you could get excessive bolt carrier speed. Well have to look into the recoil spring, Ultimately that dictates how much material can be removed. I whipped this up quick. I need to do some research on the spring rates, and see if I can build a functional model within Solid works to give a rough idea of how much we can take out.
The fact is the bolt carrier is rather bloated in weight and size, if we can take more weight out without excessive bolt carrier speed then what DDustin has currently there is plenty of material to choose from.
I was thinking one of these possible cuts. I'm on my wife's computer so crappy paint is all I have. I also don't know anything about the weight limits and bolt bounce but these cuts look like they would be structurally sound and reduce a lot of weight.
Here we go random cuts of excess material and not missing the tail buffer portion...
12-15-2013, 12:30 AM
Go easy on taking material off the top. Since the piston pushes on the top portion of the carrier, that is where much of the momentum in centered. I'm worried that taking that much mass from the top could induce a bit of carrier tilt. If that happened, there would be a whole lot of new and destructive wear. The rounded cuts on the top of DDustin's seem small enough, but I would stick to using the cuts 68 showed on the lower portion of the carrier. If that turns out not to be the case, thats great, but I would prefer to play it safe.