Umarex to make a 68 caliber, 5-shot revolver- HDR-68

[Jonnydread]

I would wager than the shell to fill ratio on .50 leans towards a thicker shell too

[BrickHaus]

My guess it paint diameter. The bolt hammering on a smaller diameter of paint proves to break less. The bolt hammering on the .68 cal paint can break a hole into it followed by the air blast which makes a mess?

I also think some of the people buying these off of Amazon are effectively getting the higher powered ones bit they aren't clearly identified.

[Brokeass_baller]

So why is the .68 version breaking balls, but the .50 is reliable?

[BrickHaus]

I got mine from MCSUS.vom and I believe they are all 7 5 joule versions.

[GanonsGrin]

So which version specifically is everyone ordering? I don’t see specs when I pull it up on Amazon other than it being in “paintball pistols”

T4E HDR .68 Caliber Revolver Training Pistol Paintball Gun Marker https://a.co/d/emaAc2k

[crazedloon]

I am just going to leave this here as a preview of what I am trying to get a bit more control over velocity and maybe efficiency etc.

I have a in grip regulator for adjustment, I have a handful of springs I will be trying as well to see if I can reduce pressure and spring tension to get a bit deeper in a 12 gram for more shots, and reduce the force on the ball to help with breaks.

[XEMON]

Shameless plug:
I have about 15 of those ready to go, but I'm gonna be to busy to ship anything till the end of next week ... I'll make a sale thread when I m ready to ship 😁

[William the Third]

I've discussed a bit my idea for a regulator for the HDR/TR50 elsewhere on the forum (might be in the members only section). I have some designs in minds, but the biggest problem is cost. I'd estimate a regulator design to be $100+, which is a hard sell for a marker that only cost ~$100. It's already a hard sell on the volumetric adjuster at $45 shipped, which only profits me enough to maybe buy dinner off of a fast-food dollar menu (well, they will eventually if I sell enough of them). Not that I'm complaining, as I didn't really do it for the money. I'd just like to eventually break even on my initial cost of getting them made.

[crazedloon]

20shots is a great shot count, what velocity are you getting on them? And I am interested to see what you have done for larger volume

I wonder if increasing chamber volume is really needed (beyond removing the restriction sleeve). Obviously there is some other factors when comparing this to a Mag, but efficiency mods on mags involve reducing the volume of the chamber. I do not believe the volume of the "chamber" on this is at least as large as a reduced volume mag.

Increased flow (not sure how to get this), reduced spring tension, and a standard pressure I think would be a good combination but that is all hypothetical.

I am super interested to see how Y'all do this however.

[XEMON]

The velocity needs to go down on the 50 cal, so ref is an option, velocity needs to go up on the 68 cal, so increasing chamber volume is one of the only route without re-designing the entire valve ...
I seam to get around 20 shot with the increase chamber (4 mags) which is good enough for me ...

But, if anyone comes up with something cool, I'll definitely give it a go 😁

[William the Third]

You should stay out of my head, it's dangerous in there! Just make sure you don't open the third drawer!

[crazedloon]

Has anyone played around with regulating this or the 50 cal version. I would think a regulator may be able to use its "slower" recharge rate much the same way the restricted flow of the valve to allow the valve on this to shut without an on/off. Then it would also allow adjustment of the velocity by pressure. I would think it may also allow you to reduce the return spring pressure which may lead to better efficiency. There should be plenty of room in the grip to add a smaller reg/12gram changer (like a cart reg or another equivalent set up) if this is indeed a decent option.


Most of the mods for higher power I have seen has been to dump more gas downrange by removing the flow restrictors and shortening the bolt internal shaft. Each of these would work but have terrible impact on efficiency.

[XEMON]

Well, whatever you make, count me in 👍
I'll make a small writeup on increasing velocity (how I did it anyway) when I get a minute, really curious to see how other people have/will do it ...

[William the Third]

I've been busy with various BS for the past month, and I see these are finally released. We're a dealer at the field, but still haven't gotten ours yet. I've got some ideas for velocity adjusters from looks of the pictures, but won't really know anything until I get me hands on one.

Humorously enough, I thought about a soft tip bolt back with the HDR/TR50, but it would require a whole new bolt (which wouldn't be a bad idea, as the stock bolts are ridiculously soft Chinesium) so it doesn't protrude when aired up. I see the HDR68 is basically the same. I've still got some ideas for both the 50 and 68, which could further increase efficiency, decrease bolt speed (the reason it's so hard on paint), and allow for velocity adjustment.

[crazedloon]

I would be interested. I assume you are opening up the valve "sleeve" to increase the volume of the chamber?