Cartridge overall length (COAL) can absolutely make a difference. My M10 with Lage upper was jamming every single round with some shorter COAL .45 rounds I was using. I loaded my next batch of .45 to a longer COAL, and the problem disappeared for the most part (I had some other compounding issues going on outside the scope of this thread). That’s another reason why it still might make sense to try different ammo.
Velocity VMAC-45 jamming with hollow points
- Thread starter gameragodzilla
- Start date
gameragodzilla
Active member
How would I modify the gun to work with guns of a shorter OAL since these are hollow points? Could bending the feed ramp work? How would I do that?
Man, I just want this to run with one particular type of hollow point and then FMJ ball. I hadn’t realized it was this difficult.
At least one reason why that type of jam happens is when the round feeds at too steep of an angle. I’m dealing with this in another gun at present.
You could try spreading the magazine’s lips apart slightly so that the rounds sit higher and have more of a straight shot at the chamber. You may just ruin the magazine though. I think if you bent the feed ramp down so it is less steep (assuming you can even do so on a Vmac), you’d risk making the bullets run up the ramp too low and crash into the edge of the barrel, especially with the flat hollowpoint tip shape.
Are you getting bullet setback into the case when it jams? That can exacerbate things as well.
gameragodzilla
Active member
A little, yeah, at least when I looked at the round. Though when I fired it, I rechambered each round and they always chambered and shot afterwards when I cycled manually. But it does seem like the jam is a bit violent.
Are there any aftermarket feed ramps I could use to give more leeway on feed adjustment? Could bending the feed ramp down and throating the barrel work?
At this point are there any gunsmiths who’d know how to get these guns running with hollow points? Velocity themselves said they’ll try but no guarantees, and Practical Solutions said they wouldn’t attempt it since they can’t guarantee either.
Practical Solutions would have been my suggestion, but you’ve already talked to Sam it sounds like. If the manufacturer offered to give it a try, I’d take them up on it.
I have seen some machined feed ramps available, but I’m not sure what they are meant to work with (M10, M11, M11/9, etc.).
I don’t know about the Vmac, but removing the barrel is not that big of a deal on most Macs. Maybe you could get someone to throat it for you.
gameragodzilla
Active member
Yeah, and their suggestion was that since the gun was set up for FMJ from the manufacturer, they didn’t want to mess with it. Which fair enough, but leaves me with little options.
Got a link for the feed ramps? Also if something gets screwed up, I wouldn’t have to buy a new entire gun and can just get a barrel and feed ramp, right? And how would I remove the barrel?
I guess I’ll try the manufacturer if there is no one else, but even they didn’t seem confident in getting it working. Is there anyone here who does have a MAC-10 closed bolt clone that does run hollow points? Would like to see the geometry there and how it differs with my gun to see if that helps.
Here is Sam's video on removing the barrel:
Here's several feedramps. I don't know which Macs they are compatible with. I suspect it is only newer clones. My M10 just has a sheet metal one. Not sure what a Vmac uses.
https://jc-arms.com/Feed-Ramps_c_22.html
If you screw up the barrel, it should be easy enough to replace. If you screw up the feedramp, it likely depends how it is setup now. If it is a welded-in sheet metal one, you might have to have someone reweld the ramp and refinish the gun. If it is just a pinned-in option like the ones in that link, it would probably be pretty easy to replace.
Hopefully you can get something to work out.
Here's several feedramps. I don't know which Macs they are compatible with. I suspect it is only newer clones. My M10 just has a sheet metal one. Not sure what a Vmac uses.
https://jc-arms.com/Feed-Ramps_c_22.html
If you screw up the barrel, it should be easy enough to replace. If you screw up the feedramp, it likely depends how it is setup now. If it is a welded-in sheet metal one, you might have to have someone reweld the ramp and refinish the gun. If it is just a pinned-in option like the ones in that link, it would probably be pretty easy to replace.
Hopefully you can get something to work out.
gameragodzilla
Active member
VMAC seems to be a piece of bent sheet metal with a feed ramp cut in, so maybe a barrel and feed ramp could be sufficient for a gunsmith to experiment? Not sure if it’s pinned or welded.
IMI imported them as well as conversion kits for the 9mm guns. Mags are externally identical.
Since the KS mags are easy to get (GG mags are between $30 and $50 a pop here so the same price) have you tweaked the feed lips? If it's going nose high a gentle tweak to the front of the lips will bring the nose down.
gameragodzilla
Active member
I see. That being said, are Uzis any better at dealing with hollow points than MACs?
And as for the mags, I have thought about it, though I have so many mags that it's kind of a pain to tweak all of them if I have to. That being said, I did box up my gun, my mags, and some spare parts, and will be sending them to Velocity. They agreed to look at the gun and see if something can be done. I've also redirected an order of my Winchester Ranger T to their shop as well so they can have 500 rounds to work with for testing. So hopefully all of that can yield some results.
Really would just like to see how many people here have successfully shot hollow points out of this gun before, or at least any kind of MAC clone. Maybe there's some specs there with regards to the barrel and feed ramp that can help.
If the velocity upper is anything like the MAC upper there is no feed ramp.
I don't shoot JHPs. Gets expensive on a FA gun that will never be used for HD. Unfortunately no help there.
Your photo looks like it is presenting the rounds high which is why I say mag tweaks. No amount of barrel or feed ramp work will help if the nose of the round is already too hight from the mag to go down the tube.
I don't shoot JHPs. Gets expensive on a FA gun that will never be used for HD. Unfortunately no help there.
Your photo looks like it is presenting the rounds high which is why I say mag tweaks. No amount of barrel or feed ramp work will help if the nose of the round is already too hight from the mag to go down the tube.
gameragodzilla
Active member
Will be sending my gun to Velocity to see. If mag tweaking is what they need to do, hopefully they can tweak the mags though that means I can’t just buy new mags off the shelf. I do have 11 mags, though, so that should last a lifetime?
And yeah, the feed ramp is on the lower receiver, not the upper. Seemed to be a piece of bent sheet metal with a feed ramp cut into it. Wonder if reducing the angle would help, but we’ll see how Velocity takes care of it. Hopefully 500 rounds are enough to do thorough testing.
If you can’t get it to work, you could go with a Glock 21 and a Micro Roni setup. It is also a mag-through-grip setup. B&T also makes a chassis for the Glock 21, but I think it is technically an SBR. I suspect either will have an easier time feeding HPs than the Vmac.
https://caagearup.com/product/mck21-micro-conversion-kit-glock-20-21/
https://bt-ag.ch/en/produkt/bt-usw-...40-20-21/#iLightbox[slider_carousel_841647]/0
Full-auto MACs are awesome, but there are better choices for semi-auto.
https://caagearup.com/product/mck21-micro-conversion-kit-glock-20-21/
https://bt-ag.ch/en/produkt/bt-usw-...40-20-21/#iLightbox[slider_carousel_841647]/0
Full-auto MACs are awesome, but there are better choices for semi-auto.
gameragodzilla
Active member
Ah, didn’t know there were compatible chassis for .45ACP Glocks. Thought they were all for 9mm only.
That’ll be a fallback option if Velocity can’t get the VMAC-45 working. Tbh, I would still prefer the MAC since I also love the gun aesthetically on top of the pistol grip, compact setup.
EDIT: Come to think of it, do any exist for 1911s. My gun is a double stack built off a Para Ordnance frame but as long as it’s compatible with 2011s or doesn’t go around the magazine well, it should work. Then I could use my existing 1911 as a braced PCC of sorts.
EDIT 2: Well my gun got shipped out today to Velocity so we’ll see how it goes. Ammo is also being sent their way. Hopefully they can work something out.
I wonder if there are also any other uppers that might feed hollow points better. I have thought about Lage uppers but from what I’ve gathered, they’re only for full autos. Semi auto closed bolt uppers aren’t really a thing. Guess if this doesn’t work, I’ll keep the VMAC as an FMJ only range toy and look at the Glock 21 chassis or hopefully a 1911 compatible chassis for my carry pistol. Hell, it would be nice to have a pistol brace I can attach via the mainspring housing, since that’s an easy part to replace on a 1911.
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A&S Conversions
UZI Talk Life Member
It is my understanding that the only difference between an open bolt M10 upper and a closed bolt is the bolt itself. So I would think that your gun smith could drill and tap your original bolt to add the Lage weight. You don’t so much need the extra weight on top for a semi, but that is the location of the charging handle of the upper. Good luck with your project.
Scott
Scott
The Lage Max-10/45 still uses the same feed ramp (that of the lower receiver) and positions the barrel’s chamber end in substantially the same spot relative to the ramp. There may be some small variations that would produce a different result, but in the big picture, it is substantially the same feeding setup. The Max-10/45 is not immune to three-point jams. I experienced them using rounds with too short of COAL as well as with some underpowered rounds.
gameragodzilla
Active member
Gotcha, so unlikely a new upper will resolve the issue. We’ll see how the gunsmith resolves my gun, then. Everything else about the gun is satisfactory to me. The welded on rails work well, the folding brace works well, the optic works well, the magazines seem to work well. It was nice to shoot at the range and I was relatively accurate with it. The only thing keeping this gun from being perfect for my purposes is it not running the hollow points I want it to.
Still wondering if anyone here has ever had theirs work with hollow points. At least that can be one source of data to look at things like feed angle, throat geometry and the like.
Still wondering if anyone here has ever had theirs work with hollow points. At least that can be one source of data to look at things like feed angle, throat geometry and the like.
I’ve never messed with hollow points in mine, though maybe I should try. I can’t imagine using it for personal defense since it is full auto, but might be fun for blowing up jugs, watermelons, etc.
gameragodzilla
Active member
Maybe next time when you’re replacing your carry ammo, you could try it.
And as you said, there should be no feeding difference between closed and open bolt MACs, right? I ask because I remember hearing someone else say otherwise but there was never any elaboration nor was he clearly an expert.
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