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Author Topic: Gauntlet parts  (Read 877 times))

Offline Treb37

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Gauntlet parts
« on: December 02, 2020, 11:50:43 PM »
Just picked up a .25 Gauntlet on sale. I know Hajimoto makes custom parts, where can I get OEM parts like barrels and uppers?
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Offline Treb37

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Re: Gauntlet parts
« Reply #1 on: December 03, 2020, 05:53:22 PM »
I guess some more info is in order. A while back I built a QB78 Ninja HPA conversion that has been working well for me. I did the laundry list of mods that were being talked about on here including the valve mods and opening the transfer port.

I filled my gauntlet straight out of the box and it leaked from the get go. 100 or so rounds in and it's still leaking at about the same rate. I have voided my warranty  8) by fully disassembling the rifle and deburring and polishing parts. I also enlarged the transfer port in the barrel to the same wire gauge drill bit as the valve. I am pretty sure the valve is what's leaking because I can hear it coming thru the breach when I first start filling, on a flat bottle. It seals up to some degree after more pressure is applied.

I inspected the valve when I had it down and it looks to me like there is an  irregularity in the valve seat and the poppet is not centered on the shaft. In other words when I burnished the valve I could see the poppet wobbling. Planning to order a new poppet kit from Hajimoto but curious if this specific problem has been seen before and if there is any fix. I thought about burnishing it with some rubbing compound to see if I could polish out the seat?

The reason for asking about parts availability is I might try converting this to a .22 cal with a different barrel and bolt.
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Gauntlet .25 STK full tune and 4500psi CF bottle

Offline Hajimoto

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Re: Gauntlet parts
« Reply #2 on: December 06, 2020, 08:58:18 AM »
Umarex parts is where you will need to go to get parts. The leak can be the poppet or the valve body o-ring. I would check replace the valve body o-ring first. I do offer tuning o-ring set that contains enough to replace the o-rings twice.


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Offline Treb37

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Re: Gauntlet parts
« Reply #3 on: December 06, 2020, 12:49:47 PM »
Thanks for the reply Haji... I have plenty of the valve body O-rings on hand from my HPA QB78 conversion which is pretty obviously where the idea for the gauntlet came from. I've had the valve out many times now and changed the seal making sure not to shave off the edges on the bottle adapter holes as well. I'm pretty sure it's the poppet seal and I'm going to order the STK kit from your website. But the valve seat appeared to have tooling marks on it which I attempted to polish out. That succeeded in slowing down the leak some. I don't think I've seen it on your tutorial videos but we used to "Flow" the valve body to get rid of the hard edge to allow smoother airflow through the port. I'd like to do that on mine but those Dremel tool burrs can get away from a guy and I want to know I can get a replacement valve body if I booger up the one I have.

I lcouldn't find a parts section on the Umarex website to order parts online....do I need to call them?
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Gauntlet .25 STK full tune and 4500psi CF bottle

Offline scion19801

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Re: Gauntlet parts
« Reply #4 on: December 06, 2020, 06:49:04 PM »
email umarex. i know i was in that boat as well. the valve body was like $10 if i recall. but that was before this virus &^^& started. can you post up some pics of the valve seat? I had the same issue. I ended up cutting small squares of fine sand paper and pushing the stem through it to help burnish polish the seat and poppet together. i had a bad spot that wouldn't seal as well. I found that with the valve all out. clean it up and assemble it and put the cage in your mouth and try to blow through the valve. wiggle the valve stem and see if you can get it to leak. which i'm sure you will. sand and polish some more, til you can get it to seal by this testing.  then reassemble just the lower tube and valve. air it up and dunk it in water. this will tell you if you have it 100% sealed up. Took me a few tries to get mine to finally seal back up using this method. mine now holds air forever.
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Offline Treb37

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Re: Gauntlet parts
« Reply #5 on: December 06, 2020, 09:59:28 PM »
I did that exact same thing with 400 then 800 grit wet dry sandpaper. Then used automotive rubbing compound to polish it. Then let it sit overnight and check pressure. I'm on round 3 of this process now and it looks like it might still be leaking. The valve seat looks pretty good to me now so I'm suspect of the poppet especially since it's not centered on the shaft. I'll get an email off to Umarex and get a valve body inbound. Maybe that and the SRK will get here about the same time...thanks for the info.
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Offline Treb37

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Re: Gauntlet parts
« Reply #6 on: December 07, 2020, 12:19:22 PM »
Fingers crossed....it looks like it held 1200 psi overnight. I'll put it back together and fill to 3K to make sure.
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Offline Treb37

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Re: Gauntlet parts
« Reply #7 on: December 08, 2020, 04:51:52 PM »
3rd time turned out to be the charm...holding pressure now. With a few tricks borrowed from my QB78 Ninja build I'm getting 918 fps with 25.39gr JSB kings with 1900 psi reg. There could be even more in it with a few more mods.

I want to see if it likes slugs because it's supposed to be my long range prairie dog gitter. I know Haji doesn't recommend slugs but the advantages are hard to ignore and every gun has it's own preferences. Anyone have a slug that's working for you?
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Gauntlet .25 STK full tune and 4500psi CF bottle

Offline scion19801

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Re: Gauntlet parts
« Reply #8 on: December 08, 2020, 07:35:04 PM »
Have you done any work to the leadin? there is a sharp edge going from the .254" breech and into the rifling. it needs to be softened. I had to with mine and i have mine doing really well with my .249-rf NOE 37gr slugs.  I'm set at about 1750-1800 psi and can stack all day at 30 yards with just a slight elevation change, then drop in my 27.2 gr pellets and undo the elevation change and right back to stacking pellets.
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Offline Treb37

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Re: Gauntlet parts
« Reply #9 on: December 08, 2020, 08:46:45 PM »
No I haven't but it takes too much force to seat the slugs. What did you use to soften the edge and did you open the leade too?
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Gauntlet .25 STK full tune and 4500psi CF bottle

Offline scion19801

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Re: Gauntlet parts
« Reply #10 on: December 08, 2020, 10:21:16 PM »
On mine, I used a small green grinding wheel in my Dremel kit that I custom shaved to an angle. It fits just under the breech size of the barrel. So say .253Ē at the metal post side of the grinding wheel, then tapered down smooth and evenly to say .247Ē on the side without the post. Basically it will look like a cone. Then I drilled a small hole to tightly fit the Dremel bit into a round wooden handle, and did it by hand lightly twisting it back and forth. You donít need a lot, but it is just to break the hard 90 degrees step that is just beyond the transfer port where the breech steps down to the bore size and the lands and grooves. Your basically shaving some of the lands beginning edge so that itís angled versus the 90 degree which is causing hard loading with slugs.
The gauntlets arenít really setup in the lead area to shoot slugs as they are mainly a pellet setup. But they can be used to shot slugs with this work on the step.
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Offline Treb37

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Re: Gauntlet parts
« Reply #11 on: December 09, 2020, 12:22:59 PM »
Well I did the exact same thing but slugs get about halfway past the transfer port before they get stuck in the rifling. The sharp edge in  the bore was only scraping the slug in one small spot. It shoots pellets so well I'm almost afraid to take it any further.
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Gauntlet .25 STK full tune and 4500psi CF bottle

Offline scion19801

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Re: Gauntlet parts
« Reply #12 on: December 09, 2020, 01:52:55 PM »
what diameter slug are you trying to use? i found .249" to be the best for me.
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Offline Treb37

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Re: Gauntlet parts
« Reply #13 on: December 09, 2020, 02:09:34 PM »
JSB knockouts .251 and FX hybrids apparently at .25. Who makes .249 slugs, NSA or someone else?
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Offline scion19801

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Re: Gauntlet parts
« Reply #14 on: December 10, 2020, 12:55:27 AM »
nsa does. but I didn't have much luck in my gauntlet with them. haven't tried hybrids or knockouts. but my NOE brass mold does well.
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Umarex Gauntlet .25, Hawke vantage 3-12x44 sf, jsar super tune kit, adjustable flex regulator, .38l bottle, rocker1 LDC

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Offline Treb37

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Re: Gauntlet parts
« Reply #15 on: December 10, 2020, 02:07:24 PM »
I see...so you are casting your own then. I've never heard of NOE before.
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QB78/ ninja .22 full valve mods 35 fpe
1st gen XS60c
Gauntlet .25 STK full tune and 4500psi CF bottle

Offline Madd Hatter

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Re: Gauntlet parts
« Reply #16 on: December 10, 2020, 02:24:28 PM »
Noe has a lot of air gun molds. Both pellet and slugs.

https://noebulletmolds.com/site/shop/
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