Barrel/gas system length

[wildcatter]

Though I'm waiting on my upper (4 weeks today) I have read that the front block is non-functional.
Hoot

2x, but can be made functional and why would one do that?

Answer: When trying to ring out the performance one needs to increase the powder volume and use slower burn rate powders. This must not be done by the faint of heart or the inexperienced, there are dangers involved in doing this and if "You" break something, only "You" are the blame!

The slower powders, lower bullet speeds and pressures, allowing you to increase the powder amount, again caution. But much can be gained or lost (like your weapon or health), by looking for that wall.

But there is a Wall that will be reached long before you get to the Speed/Pressure Wall. Long before you get to the end of the trail I'm now describing, the action will start opening way too soon and start ripping off the rims or quit functioning altogether. In order to get pass this, the Dwell Time must be changed. Using the extra gas block on the 20" inch barrel, is the trick. You guys can do the same on the 16", by installing a new rifle length gas block and accompanying gas tube or using the supplied gas block and coming up with a way to block that gas port, pick one they are all pretty much going to work.

But what of the carbine length gas port? Many things and ,methods could be used to block it, but for us 20" guys, we've got a quick little fix. By rotating the Dissipater Gas Block (The name for the carbine length gas block and is the gas block on used on both Factory 20" and 16" weapons.) 180 degrees and then reattaching. I then run the Rifle length tube, right over the upside down Dissipater. Bingo end of that Road and on to another road, which is Speed and we all know Speed Kills, just make sure it isn't you, because you went to far up the powder scale.

By finding a home for the dissipater gas tube on the weapon its self, you can quickly and easily revert back to the dissipater system, if you want to revert back to Factory ammunition.

But here is the Holy Grail for wanting to do all of this. Keep in mind that the shortening of the 45 Pro to be able to use the pointed bullets, pressure curves changed allot. But, in the 45 Pro (not in the 450 Bushmaster ammo), and for years my standard loading was 230gr bullets at 3000fps!

[Hoot]

...snip...But, in the 45 Pro (not in the 450 Bushmaster ammo), and for years my standard loading was 230gr bullets at 3000fps!

How did you de-burr the hole you drilled for the rifle length tube in the barrel? Did you lap it out with a slug or what? Second, did that loading put a serious hurt on your shoulder, or did the brake finally kick into gear with the slower burning powder? Guessing that you used around 40gr of powder. With a 230 gr bullet at 3k fps. The recoil calculates to double the factory load.

Hoot

[BD1]

WC, have you had any issues with the presence of the unused port? My interest would be in going the other direction, locating a new port even closer to the receiver so the action would operate using 400 grainers at 1,050 fps. Once the second port is installed, it seems like it would be a pretty simple thing to switch back and forth as needed. Here in SC we are allowed to hunt with suppressors.
BD

[wildcatter]

...snip...But, in the 45 Pro (not in the 450 Bushmaster ammo), and for years my standard loading was 230gr bullets at 3000fps!

How did you de-burr the hole you drilled for the rifle length tube in the barrel? Did you lap it out with a slug or what? Second, did that loading put a serious hurt on your shoulder, or did the brake finally kick into gear with the slower burning powder?

Hoot

Done do anything for the burr. The burr is so slight, it burns off with the first shot and in so doing creates no problems what so ever. Something else, when you drill the port, wrap enough tape around the drill shank, strategically placed so that when the drill brakes through, into the barrel, the tape stops the forward movement and doesn't strike the far side of the bore.

As for recoil putting the Hurt on ya, lol. Because of this problem, long years ago, I starting using a Past Recoil Pad (http://ecx.images-amazon.com/images/I/3 ... AA300_.jpg), under my field coat and even while hunting. Today there are other solutions. Now days, I use a Lead-Sled on the range and in the Lab.. But I've got to tell you-all, GunNut (Gunny) has Developed and is Perfecting, an over-all system that is very astounding and I for one plan to send him all of my weapons of Mass-Destruction, that kick like like a Mad as the Dickens Mule, and beg him to fix them!! Now, I don't want to steal his thunder and the News Release timing is up to him, but knowing what I know of his work, you'd start another thread of names, that are standing in line waiting for him to fix your rigs. Incidentally, now that I think about it, a new waiting list of names, is not a bad idea. When his creation hits the market, there will be long lines and for once you'll have an opportunity to get to the front of the line!! I love this Board! This is the actual gathering place for engineering type guys, that aren't afraid to risk life and limb to travel to the Stars, without all the crying and cursing found on the other channels, are willing to police it from the trolls and get the real work done and all the while, supporting each other. Wow, this is developing into something. Now, I envision this brotherhood, at some point, occasionally meeting for reunions in the Mudders HQ (his living room, wink)..t

[2zero6]

wanna trade?

do you have a 16" or 20" and how many rounds fired through it?

i have a 16"

it has fired a grand total of 5 rounds.

i was talking about just the gas block.. not the whole upper. i like my 16"

Yeah I will look for it tonight and shoot you a PM.

[2zero6]

After looking at my spare the false forward gas block On the 20". It is a normal low profile gas block that will function. It is an exact copy of the one hidden under the hand guard. Hope this helps guys.

[wildcatter]

WC, have you had any issues with the presence of the unused port? My interest would be in going the other direction, locating a new port even closer to the receiver so the action would operate using 400 grainers at 1,050 fps. Once the second port is installed, it seems like it would be a pretty simple thing to switch back and forth as needed. Here in SC we are allowed to hunt with suppressors.
BD

Sub-Sonic.. Sho-Nuff BD, you can go closer, but port size becomes critical and there can be some slight problems, that can be overcomed by tweaking. I took some cheapie 500gr 458" SWC's and used something like a compressed load of 870, with a super-stout LeGendre Side Crimp, to get them to seal in the chamber, on a std length gas system and got things to function nicely and the speeds were slightly over 1000fps. With a port closer to the chamber, you might be able to use faster powders than 870 and thus seal the case better. Lemme know, I have a test jig, I made up, that will tell you where to locate the port and how big to make it, for any given loading. If ya need it I'll send it over. You'll need to get your load down pat and then decide where the port goes and how large it needs to be. But 400grainers with something like blue dot or maybe 2400, loaded down to 1050fps, those might just function the 16" system just fine, try it out and holler back..t

[BD1]

Thanks WC, a jig would be mighty handy. I'll work on the load. I have some 860 I can play with, but in my experience with other calibers, low velocity/pressure loading with the real slow ball powders can be a pretty dirty affair, lots of soot and unburned grains to gum up the works. Also, extreme velocity changes as the temperature changes. I'm hoping for a load that will will burn 95% or above to keep the gas system and suppressor going as long as possible between cleanings.
BD

[wildcatter]

Thanks WC, a jig would be mighty handy. I'll work on the load. I have some 860 I can play with, but in my experience with other calibers, low velocity/pressure loading with the real slow ball powders can be a pretty dirty affair, lots of soot and unburned grains to gum up the works. Also, extreme velocity changes as the temperature changes. I'm hoping for a load that will will burn 95% or above to keep the gas system and suppressor going as long as possible between cleanings.
BD

Yeah you're right. With those cast bullets, you've got allot to crimp into, A very-very heavy LeGendre Side Crimp goes along ways to cleaning the powder burn up..t

[wildcatter]

I just got a question as to why the 450 Corvette.

It can be used to function factory "Plus" your experimental Hot Loads. Plus the Corvette smooths out the functionality of the 450 system, not that the 450b functions bad, no not at all, but we have seen some hic-ups right here, that the the Corvette system cures.

I wanted to say and point to this for future thinkers..

..t



NUFF SAID!!!!!