I have a light leak, 300 psi overnight on my bottle USFT. Just converted by Tim. Does anyone have a schematic for MAC1 rifles?
my guess is that the regulator is the issue….
my guess is that the regulator is the issue….
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MAC1 USFT Analysis/Overview
- Thread starter Franklink
- Start date
Sorry that I can't help but I've never had the need to go in mine. Also, mine does not have the regulator, although if I was a betting man......your suspicions of the regulator are likely correct.
This link has another link that contains a photo of some of the parts laid out, and, as Strever says in the link, that's probably as close to a diagram as you're going to get.
https://www.airgunnation.com/topic/mac-1-usft/#post-65964
This link has another link that contains a photo of some of the parts laid out, and, as Strever says in the link, that's probably as close to a diagram as you're going to get.
https://www.airgunnation.com/topic/mac-1-usft/#post-65964
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Hello Frank - the gun did not leak before I had Tim change it to the bottle / regulator set up so yes, I feel that the regulator is most likely to blame. If I dig in to the regulator then I'll have to take pictures because is suffer from CRS and others might be interested.
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Have you discussed this with Tim already? He likely can can help you out most easily, and knows more about your gun than most readers here.
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Havent used a converted one but the reg is a common stack washer Ninja type, plenty of vidios abound.
The seals in the conversion parts might be well worth looking at?
John
The seals in the conversion parts might be well worth looking at?
John
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Franklin and other contributers, thank you for the wealth of information. I didnt realize that people still liked the unregulated version. Is the ungregulated version accurate enough for benchrest like the regulated versions?
Here is my new baby. It came with a Nikko sterling 10x50x60 scope. I can see nail holes at 100 yards! WOW!
Here is my new baby. It came with a Nikko sterling 10x50x60 scope. I can see nail holes at 100 yards! WOW!
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Awesome rifle! Thanks for sharing photos of yours. It's always cool to see a different one and how they're configured. I can't say that I've ever seen two identical USFTs. They seem to always have slight differences here and there.
As for your question about if the unregulated version is accurate enough for benchrest I can't help much there as I don't shoot benchrest. I would assume that as long as you only take shots within the pressure that you know to produce consistent fps, it shouldn't be a problem. But again, I don't know if there are rules in benchrest about how often you can fill up the gun or how many shots without a fill you need to shoot a match.
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I haven't updated this for quite a while since it has been quite a while since I shot the gun. I DID however, shoot it this past weekend and wanted to share how that went.
We had a field target match over in western NM.
www.airgunnation.com
I knew going into the match that if I shot Open class I would be the only one in that class. So I had made plans to shoot Hunter using a different gun. I practiced for a couple hrs on Thursday and again on Friday, getting acquainted with and doping out the other gun. Friday evening though, I ran into some slight flyers with the gun I was going to use for Hunter and decided I need to learn that barrel a bit better (cleaning regimen, pellet lube, etc.) and pulled out the "backup gun" USFT from the truck right before dark on Friday night. I shot the gun a bit last month just plinking, but prior to that had not shot it since the AZ state field target match back in October. Well, that 15 minute dope verification on Friday night was completely uneventful. Ole reliable USFT was stacking them, using the same dope and scope zero that I've been using for literally a couple years.
Went through and shot the match with the USFT, 56 shot match and I was just enjoying it, squadded with my boy. We were having all kinds of fun shooting and moving through the course. I knew I was doing okay but somehow the gravity of being so close to another perfect match didn't hit me until the last lane. I skimmed over my score card and it hit me, "I'm four shots way from clean!" Well, I knocked the first two down, so now I'm two shots away from a perfect score. Aaaand......I shanked the first shot on the far target. Just got nervous and jittery and yanked the trigger and gun and flat out missed. Got myself composed and knocked it down the second time but finished out with a 55/56, just that one shot away from clean.
(I couldn't have just used the USFT for Hunter class because the scope on it only has yardage marks for 50x, not the Hunter legal 16x. In fact, that scope doesn't even have a mark for 16x. Further more, the shooting sticks I use to shoot from Hunter position have too much flex for a heavy gun like the USFT.)
Just another testament to the USFT's reliability. Other than the 15 minutes the night before the match I had only shot the gun one time in the prior 8 months. Pull it out of the case and proceeded to shoot a nearly perfect score. And the miss wasn't even the guns fault. Absolutely awesome consistency and 100% reliability right there. I certainly wasn't practiced up so it speaks much more to the reliability of the gun and it's maintaining poi than to my trigger pulling skills.
Amazing guns these USFTs. Simply amazing.
We had a field target match over in western NM.
Results - Southwest Airgunners June 2022 Match Report
We had another great match this weekend up around 8600 feet above sea level in the cool pines. The weather was great, with threats of afternoon monsoon thunderstorms building up each afternoon but never quite materializing. We got a few spits and sprinkles but not enough to even settle the dust...
www.airgunnation.com I knew going into the match that if I shot Open class I would be the only one in that class. So I had made plans to shoot Hunter using a different gun. I practiced for a couple hrs on Thursday and again on Friday, getting acquainted with and doping out the other gun. Friday evening though, I ran into some slight flyers with the gun I was going to use for Hunter and decided I need to learn that barrel a bit better (cleaning regimen, pellet lube, etc.) and pulled out the "backup gun" USFT from the truck right before dark on Friday night. I shot the gun a bit last month just plinking, but prior to that had not shot it since the AZ state field target match back in October. Well, that 15 minute dope verification on Friday night was completely uneventful. Ole reliable USFT was stacking them, using the same dope and scope zero that I've been using for literally a couple years.
Went through and shot the match with the USFT, 56 shot match and I was just enjoying it, squadded with my boy. We were having all kinds of fun shooting and moving through the course. I knew I was doing okay but somehow the gravity of being so close to another perfect match didn't hit me until the last lane. I skimmed over my score card and it hit me, "I'm four shots way from clean!" Well, I knocked the first two down, so now I'm two shots away from a perfect score. Aaaand......I shanked the first shot on the far target. Just got nervous and jittery and yanked the trigger and gun and flat out missed. Got myself composed and knocked it down the second time but finished out with a 55/56, just that one shot away from clean.
(I couldn't have just used the USFT for Hunter class because the scope on it only has yardage marks for 50x, not the Hunter legal 16x. In fact, that scope doesn't even have a mark for 16x. Further more, the shooting sticks I use to shoot from Hunter position have too much flex for a heavy gun like the USFT.)
Just another testament to the USFT's reliability. Other than the 15 minutes the night before the match I had only shot the gun one time in the prior 8 months. Pull it out of the case and proceeded to shoot a nearly perfect score. And the miss wasn't even the guns fault. Absolutely awesome consistency and 100% reliability right there. I certainly wasn't practiced up so it speaks much more to the reliability of the gun and it's maintaining poi than to my trigger pulling skills.
Amazing guns these USFTs. Simply amazing.
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Nice shooting Frank!
At the top of the page someone was asking about a bottle conversation gun leaking from back in April. I should have taken more pictures when I had mine apart this week.
Disclaimer. I have no idea if what I did was correct. I am ham fisted knucklehead.
Mine had a chunk out of the oring on the red part right next to the black threaded section where the Huma is. I found orings at a local fastener supply store. I believe they were #27.
The white ring on the ninja side is I think is a 90 durometer o-ring. Not 100% sure. It has a top hat that if tight you can’t get into the tube. But it has slots. So I put on the new black orings and slit it together with the top hat a little slack.
After installing the four retaining bolts I was able to use a long screwdriver to snug up the top hat. This clamps the 90 dur oring up against the tube. Be aware of the threaded center portion of the top hat. If it is out too far there will not be enough room for the Huma and the four main body bolts won’t fit.
I did not pull apart the ninja or remove the Huma. After finding the big chunk out of the one oring I assumed that was it. I have had it back together for about 24hrs and it is still holding the same pressure. Fingers crossed.
The unregulated tube guns are much simpler.
At the top of the page someone was asking about a bottle conversation gun leaking from back in April. I should have taken more pictures when I had mine apart this week.
Disclaimer. I have no idea if what I did was correct. I am ham fisted knucklehead.
Mine had a chunk out of the oring on the red part right next to the black threaded section where the Huma is. I found orings at a local fastener supply store. I believe they were #27.
The white ring on the ninja side is I think is a 90 durometer o-ring. Not 100% sure. It has a top hat that if tight you can’t get into the tube. But it has slots. So I put on the new black orings and slit it together with the top hat a little slack.
After installing the four retaining bolts I was able to use a long screwdriver to snug up the top hat. This clamps the 90 dur oring up against the tube. Be aware of the threaded center portion of the top hat. If it is out too far there will not be enough room for the Huma and the four main body bolts won’t fit.
I did not pull apart the ninja or remove the Huma. After finding the big chunk out of the one oring I assumed that was it. I have had it back together for about 24hrs and it is still holding the same pressure. Fingers crossed.
The unregulated tube guns are much simpler.
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Must have been a difficult project, seeing what could be a bottle of bourbon at the top left in the first picture.
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It was leaking with that chunked oring. I replaced the black orings, the white 90 duro ones seemed fine so I reused them.
Is yours a bottle or tube gun?
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Indeed great barrels those early HW's .... Purchased one ( 26" 6 groove .22 cal ) from LD in @ 2016-17 or so from him at the Placerville Airgun expo.
Have been shooting with LD and on occasion Tim over the past 10 years here in California. Seen MANY a match won with these rifles.
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@wildcj5 - indeed a bottle gun.
just replaced the barrel with a full length LW slow poly with a Strip-T and it shoots better further out than the carbine barrel it was built with. Will check those o-rings after next weeks match and I secure a set
btw - how quickly was your gun loosing pressure?
just replaced the barrel with a full length LW slow poly with a Strip-T and it shoots better further out than the carbine barrel it was built with. Will check those o-rings after next weeks match and I secure a set
btw - how quickly was your gun loosing pressure?
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It wasn’t leaking super fast, 100 psi a day. But once it was empty it was a pain to get it to take air.
Not sure if I will explain this right but the gauge on the tube was reading 1,300 psi. I think that is what the Huma is set at. After a shot the tube gauge would drop and take 30 seconds to a minute to recover.
After changing out the orings the tube gauge is back to reading 1,600 psi. That should be the reg setting on the ninja. After a shot the gauge is back at 1,600 in a second or two.
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Interesting, mine is leaking a little quicker but I have no problem filling it up from empty. The tube gauge stays close to the 1300-1400 it is set for. we Will see when I dive in. Now i just need a list of the o rings needed
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Ditto! @wildcj5, Thank you very much for adding to the thread. My intent for this was to serve as a sort of long-term resource for folks interested in USFTs. And your contributions are spot on with that intent, specifically in the bottle version. Which is great b/c I don't have any insight there. Thank you sir.
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So I recently had a head scratching experience 
with a comparison between the USFT and another polygonal barreled .177.
The USFT is referenced various times in this other discussion, but the takeaway is here: https://www.airgunnation.com/thread...ue-to-barrel-differences.1269811/post-1309005
That experience prompted me to finally measure the twist rate of my USFT. Used this simple method:
It was a a bit interesting b/c there isn't 36 inches of barrel for the flagged tape to make a complete revolution. The barrel is just under 24 inches if I remember correctly. I had to do 1/4 and 1/2 revolutions (of the flagged tape) and measure distance on the cleaning rod and then do the math for full revolutions. Repeated the process a handful of times and arrived at a twist rate of 1:36 inches. Lothar does make a 1:36 polygonal .177 barrel with a 16mm OD and Tim McMurray even has them on his website, advertised as a "slow poly."
So, is the 1:36 twist rate the magic or is there something else about this barrel that makes it such an amazing shooter? I can't answer that question, but would REALLY like to figure it out.
with a comparison between the USFT and another polygonal barreled .177. The USFT is referenced various times in this other discussion, but the takeaway is here: https://www.airgunnation.com/thread...ue-to-barrel-differences.1269811/post-1309005
That experience prompted me to finally measure the twist rate of my USFT. Used this simple method:
It was a a bit interesting b/c there isn't 36 inches of barrel for the flagged tape to make a complete revolution. The barrel is just under 24 inches if I remember correctly. I had to do 1/4 and 1/2 revolutions (of the flagged tape) and measure distance on the cleaning rod and then do the math for full revolutions. Repeated the process a handful of times and arrived at a twist rate of 1:36 inches. Lothar does make a 1:36 polygonal .177 barrel with a 16mm OD and Tim McMurray even has them on his website, advertised as a "slow poly."
So, is the 1:36 twist rate the magic or is there something else about this barrel that makes it such an amazing shooter? I can't answer that question, but would REALLY like to figure it out.
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