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gotin
11-29-2011, 07:32 PM
I got a Mac-10 .45 last week and loaded 200 rounds with Lee 230 gr round boolit with 4.6 gr, 4.8 gr and 5 gr of Bullseye, 5 gr being the recommended "standard" load for 230 boolit.
The gun cycled with all loads, with 4.6 gr it was difficult to control, with 5 gr it was all over the place.
I'm thinking of reducing the load ever further, trying to make it easier to control.
I've heard about some powders burning erratically at very light loads (is Bullseye one of them?) and don't want to go that low, so what is the safe minimum? I know it will have to be strong enough to cycle the bolt, I was thinking of loading in 0.2 gr steps of 50 rounds and going as low as 3.5 gr.
Another thing - the chamber of my gun is "generous" in its size and the brass seems expanded a little more than normal - how many reloads do you get out of your subguns?

williamwaco
11-29-2011, 08:18 PM
Well, a blast from the past.

I have owned three MAC 10's. I never found any way to control the .45. The 9mm had a 12" suppressor. If you held the suppressor, It was semi controllable.

The real joy was the .380. It was a blast to shoot. Expensive. It was difficult to reliably control the trigger enough to fire less than a full magazine. the cyclic rate was 1200 rounds per minute. ( 20 rounds per second ) 1.5 seconds to empty the 32 round magazine.

Controllable: At 10 yards, you could empty the entire clip into a paper plate.

x101airborne
11-29-2011, 08:19 PM
My first question on your ingram is .... is it full auto or semi? Second.... Do you have the optional barrel extension that came with some of the guns? Are you using the ingram with the buttstock attachment or as a pistol? As far as your chamber, I know what you are saying, but it was intended and designed to be a full auto weapon. When they made them semi auto, they continued the sloppy chambers to gurantee feeding. What kind of groups are you getting and what are you trying to accomplish with it? If you are just spraying targets to 25 yards with full auto, there are more techniques to firing that weapon that will make more difference than the load. Precision shoulder firing that ingram at full auto will definately be a spray and pray option. Single firing it using it as a pistol, your boolit is already out by the time you experience recoil, so.. cycling is the only consideration beyond grouping. My 1933 Thompson "Chicago Typewriter" also has a huge chamber. It climbs like HE!! shoulder fired full auto also. 25 yards full shilouette of a man, I get about 4 rounds on target and that is it. Tuck the buttstock under the arm and wrap a rag around the rear of the barrel with your hand on top to hold it down and you can really mess up a 5 pound coffee can at 25 yards for 30 full rounds. I would like to help, but need more information on your question.

noylj
11-29-2011, 08:31 PM
I do not know of any fast pistol powder that has any issue with light loads.
Bullseye et.al. can be downloaded as low as you want.
The first powder that is so slow as to have a problem with light load is 296/H110.
IF you want a light load, you should always go down to a faster powder. You are already using one of the fastest powders.
Remember, Bullseye shooters have been loading light charges of Bullseye probably since it first came out (1890's or 1900's).

canyon-ghost
11-29-2011, 08:38 PM
I've loaded Bullseye light, it will just slow down.

chboats
11-29-2011, 08:38 PM
I have shot a lot of 45 ACP loaded with 3.5 Gr of Bullseye. It cycled my 1911 just fine. Don't know if it would cycle a Mac 10, It is a very soft load, less than 700 fps.

Carl

hk33ka1
11-29-2011, 08:49 PM
The story I heard about light loads was some slow (if I recall) rifle powders could but were never proven to, produce higher than usual pressure in light loads.

The idea was all the powder might burn at once rather than the primer lighting one end of the powder column and burning to the other in a few micro seconds like in a normal %80 full case.

gotin
11-29-2011, 09:18 PM
It is a full auto ingram.
I shot at a plastic barrel from 10 yards. In semi it will group easily in a fist sized area. In full auto the first round will hit where I aim at, the second will be a foot to the right and half a foot up, the third will be out of the target. I used the extendable butt stock.
It came with a steel shroud that screws to the barrel and it provides somewhat better grip, but it is still far from enough. Will a suppressor make a noticeable difference?
I am looking ant the Lage slow fire upper, I don't know how that will effect the controllability.
Can you elaborate more on the technique with tucking the butt stock?

gotin
11-30-2011, 02:30 AM
I just cleaned it and there was something weird I noticed.
I shot water dropped, 1/3 clip on/ 2/3 stick on wheel weights 230 grain boolits, lubed with Lee Alox. There was little leading on the barrel, mostly along the grooves, but the shroud, that screws on the barrel was something else. Right where the barrel ended it had a solid coating of lead that was approximately 1 mm thick. It extended for about an inch and I scraped it off easily.
I have never seen anything like this before, solid lead.

x101airborne
11-30-2011, 06:30 AM
Good mornin.
Well, your climbing is really just one of those things..... it is a full auto 45, LOL. Sounds like you are getting about what mine did and my dad's does. Average. As far as the leading.... What I envision happening is when the boolit is exiting the barrel it is trying to expand to fill the diamater of the extension and causing leading as the gas cuts around the base of the boolit. As pressure is reduced or bled off, the leading gradually diminshes. This would explain how you are able to easily remove it from the shroud.

I have not really noticed a supressor making a difference on climb. DEFINATELY dont attempt to hold on to or put any force on the supressor in any way. Shooting your baffels is usually an expensive mistake. And you typically get these tiny pieces of supressor imbedded in your skin. Dont ask me how I know.

I have never used the lang slow fire upper so really dont have any experience to relate. As for the buttstock technique, the one I use is a wooden quick detatch job. It is heavy and comforftable and I use it mainly to tuck it in my underarm. With a rag wrapped around the barrel extension and an over hand grip I can maintain the weapon pretty well. I am using a laser designator rather than conventional sights.

If I may give you a matter of opinion to contemplate...... I have been using / maintaining and experiencing full auto weapons for nearly 16 years now. As the unit armorer for 101st, I have seen some very professional weapons and gotten to experience them in all types of situations. The ingram is one that actually benefits from a FASTER cyclic rate and a shorter stroke. I know that sounds like horse mess, but really if you got to try it, it works. Lightening up the bolt mass helps a whole bunch also. Find a machine shop that will help you out and get that bolt milled down. That is the main secret of the accuracy behind weapons like the MP-5 and the converted scorpions and such in full auto. That and short, controllable bursts. Heck, thinking about it, I really cant think of any weapon that couldnt benefit from a diet and a good stroke job. Replace the main recoil spring too will help a lot. Those things really take a beating quick with even moderate firing.

gotin
12-04-2011, 03:41 AM
Today I shot different loads, started at 3.5 gr of Bullseye over 230 gr lee, lubed with Alox, gun cycled without problems, speed was around 700 f/s. There was leading but not much.
The gun cycled with all loads up to 4.4 gr.
I shot 400 rounds today, at first there was little leading.
At the end though there was a lot of lead covering the whole length of the barrel.
This is the first time I use the alox for lubing, for my 38 and 40 I use 50/50 beeswax and vaseline and never had leading problems.
The boolits were water dropped 2/3 stick-on weights and 1/3 clip-on weights, the same alloy I shoot in .40 at 850-900 f/s without any leading. The boolits are as cast, .453.

bowenrd
12-04-2011, 04:07 PM
I just cleaned it and there was something weird I noticed.
I shot water dropped, 1/3 clip on/ 2/3 stick on wheel weights 230 grain boolits, lubed with Lee Alox. There was little leading on the barrel, mostly along the grooves, but the shroud, that screws on the barrel was something else. Right where the barrel ended it had a solid coating of lead that was approximately 1 mm thick. It extended for about an inch and I scraped it off easily.
I have never seen anything like this before, solid lead.

Was it boolit lube buildup and not lead??

MtGun44
12-04-2011, 04:41 PM
+1 with Williamwaco on the .45 Mac 10. I got to shoot one a number of years ago, without
the suppressor. I can't imagine a more useless gun, at least in full auto. I am a very
experienced 1911 shooter, have no trouble double tapping consistently, with both rounds
striking very close on the target with a 1911.

With the Mac 10 - I was quite frustrated, third round in full auto was always into the
ceiling baffle in the indoor range I was shooting on. Fortunately, it was owned by the range
owner and he was standing there (laughing) as I tried vainly to even partially control that
thing. Maybe there is some tecnique that works, but I didn't discover it on my one short
session with the gun. Tried holding down on the strap with off hand, gripping bottom of the
mag with off hand, gripping front of frame (scary, because of muzzle proximity and the
radical motion of the gun when fired.)
If you can control this gun in full auto, you're a better man than I. My impression is that
without the long supressor as a handle it is just uncontrollable in full auto.

Good luck with the lower loads - I think I'd look at 155 gr SWCs as these are the lightest
that I am aware of that could feed through a self loader.

Bill

mpmarty
12-04-2011, 04:47 PM
I shot mil surp hard ball in mine. With the strap over my neck and pushing down on the false supressor I could get two or three rounds reasonably close to the target. After that it was anybodys guess where they went. Worthless for any serious work but fun to shoot anyway. I wish I'd have kept it. It was an early open bolt model which made first round hits very hard to do as the bolt slammed forward and disturbed the aim when the trigger was pressed. I understand the later closed bolt type was more controllable.

gotin
12-04-2011, 09:58 PM
I just slugged the barrel, it is 0.4525, my boolits barely touch the sides of the thing.
I will wait for the Lage upper, hopefully their barrels are smaller, if not I guess I'll have to leement the mold. It did the trick with a sticky .38 mold.
For now I'll skip the Lee crimp die, maybe it will help a little.
Shooting the thing is not easy, at least now I can get 8-10 bursts from one magazine and like I said, the first round hits where I aim (somehow the lurch of the bolt is compensated by the recoil I guess), then the next 2-3 rounds group together in about 5" area about 10" above my aim point. This is with the heavy SS barrel extension attached - it serves two purposes, adds extra weight to the front and provides safe way to hold the front of the gun.
Shooting AR15 after that is like shooting with a squirt gun - light, no recoil, boring.