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Post by Wild Bill on Nov 16, 2021 15:25:42 GMT
Well I managed to get an opportunity to chronograph and shoot the gun today. Firstly the chrono' results, I got a average of 332fps over the course of 66 shots, so basically a +15fps increase. Not too shabby and an increase is always welcome. Generally the results were far more consistent when compared to the smoothbore barrel, the lowest recorded fps was 311, with the highest being 363fps. Happy with that.... Secondly the accuracy results, absolutely incredible ! Once I dialled the sights in she was putting 4 shots out of 6 in the same hole at 5m, with the other 2 being just 2-3mm from the edge, all that was done two handed, unrested and obviously in single action. I should point out that the accuracy with the smoothbore barrel was prettydarn good to begin with but this takes it to another level, I was consistently losing the pellet holes in the 10mm black circles that I use for zeroing in the gun. If I get a chance tomorrow I'll do some proper target shooting on some 14x14 paper targets and throw up the results, that way you can see for yourself. My next project with the gun is to strip the innards out of it and fettle the valve to hopefully increase the power a little more. That sounds like a great improvement Shaun.
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Modski66
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Post by Modski66 on Nov 16, 2021 15:30:42 GMT
I am guessing a new avatar might be on the cards!
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Post by HeadHunter on Nov 16, 2021 16:23:34 GMT
I am guessing a new avatar might be on the cards! Don't tempt me with good ideas, I'm easily led.....lol
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Post by HeadHunter on Nov 17, 2021 15:20:42 GMT
Well I couldn't help myself, curiosity got the better of me and I stripped the gun down completely. Lubricated all the moving parts with silicon & PTFE grease and stripped the valve down, I've enlarged the ports in the valve stem slightly-ish and will give it a shot over the chronograph tomorrow and see if it has made much of a difference.
Internally she is completely different to any other CO2 replica revolver on the market, it's good to see that they didn't just rehash an existing revolvers innards and squeeze it into a newer frame ! The valve is a completely new design, the valve stem is approximately 30% longer than a DW715 one and only has two very small ports in it. The valve face doesn't even have a silicon seal on the cylinder end like the original Dan Wesson or even the later DW715 valves have. The hammer spring is an almost identical design to the DW715, which doesn't bode well for the length of time it'll work for but only time will tell if they managed to rectify that manufacturing problem too. The cylinder stop is made of metal, which is a big plus point as I'm sick of seeing plastic ones in certain guns and it goes a long way to explain the cylinder's solid lock up when cocked. The cylinder to crane spindle was bone dry and benefited tremendously from having a very light coating of lubrication on it, I would recommend doing the same to anyone out there who's thinking of getting one, it just feels so much better, more fluid rather than slightly loose, if you get my drift.
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Ade C
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Post by Ade C on Nov 17, 2021 20:48:49 GMT
I was quite impressed with the valve design. When the hammer hits it the transfer port moves forward and engages with the seal in the back of the shell. Gamo used a similar design in the R77. I'd imagine the rifled barrel would make it reasonably accurate at longer range?
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Post by HeadHunter on Nov 18, 2021 8:18:55 GMT
I was quite impressed with the valve design. When the hammer hits it the transfer port moves forward and engages with the seal in the back of the shell. Gamo used a similar design in the R77. I'd imagine the rifled barrel would make it reasonably accurate at longer range? Most CO2 replica revolvers utilise that system Ade, with the exception being the Colt SAA and the Remington 1875. When the hammer falls onto the valve stem it pushes it forward which opens the transfer ports and at the same time bridges the gap between the valve face and the cartridge, although some are better at it than others because they have a longer 'throw'. The rifled barrel certainly has proved itself in the shorter 5m range, hopefully I'll get a chance to do some 10m+ testing in the not too distant future but unfortunately my indoor range is limited to just 5m and I ain't keen on the cold, hence why I moved back home from Scotland, yeah I know I'm a "Soft Southerner", lol.
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Modski66
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Post by Modski66 on Nov 18, 2021 9:48:27 GMT
I think the R77 had an extra 'floating' part to the system that was driven forward by co2 pressure for deeper engagement.
The Umarex valve used on the 586/686 and some of the revolver-matics have a sprung loaded brass transfer port inside an expansion chamber that lightly presses against the back of the mag when at rest.
During a shot, the expanding co2 will push the brass bush hard up against the back of the magazine, which will itself push against the breech reducing gas losses. By no means a perfect seal, but keeping the interfaces hard metal rather than soft rubber reduces friction when the magazine rotates.
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Post by HeadHunter on Nov 18, 2021 12:00:40 GMT
HOLD THE FRONT PAGE....The first test with the gun firing pellets gave me an average of 307fps The second test with the new rifled barrel gave me an average of 332fps (+25fps increase) The third test after fettling the valve gave me an average of ( drum roll please) 388fps (another +56fps increase) So all in all, what with the rifled barrel and a valve rework I got a combined increase of 81fps over the original standard results, all these tests were performed with the exact same pellets (RWS MK 4.49mm 7 grain flat head lead pellets). That's a guesstimated increase of around 26% over the standard velocity, well worth all the work involved ! More information on the latest chronograph results,
Highest 426fps Lowest 361fps (which was 2fps less than the highest recorded on the previous test with the rifled barrel fitted) Average 388fps 3.17 Joules or 2.34fpe (over the course of 72 shots) To say that I'm " over the moon" with the results is a bit of an understatement indeed This bodes well for the S&W-29 (when we finally get hold of one), as I can't see the internals being any different to the S&W-629 Classic, so logically the same improvements should be possible. NOTE - I have noticed another small 'something' that I'm away to methodically check before posting anything about on here, if I'm right, it will be important information for anyone thinking about purchasing either of these two new S&W handguns (29 & 629) and something that I've missed in the review.....oops (*embarrassingly red faced*)
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CaptDAR
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Post by CaptDAR on Nov 18, 2021 12:33:39 GMT
Phenomenal increase. Need to look into the valve in my 29.
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Modski66
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Post by Modski66 on Nov 18, 2021 13:07:03 GMT
I think a lot of the fps improvement with the barrel swap has come from the increased bore of the forcing cone. As supplied, the exit bore was 4.4mm - fine for the intended BB projectile, but the amount of force I had to exert on the pellet to push it through and compress the 4.62mm pellet skirt was considerable.
Anyone planning a rifled barrel conversion will need to address this, as after compression the pellet completely misses the rifling. The cone seemed to be a hard sintered item, and was very difficult to drill, even on my lathe; it is not something I would like to try with a hand held drill!
But as Shaun has documented performance at every step, it is clear to see the valve porting is well worth contemplating for owners of this pistol.
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Post by HeadHunter on Nov 18, 2021 14:29:44 GMT
NOTE - I have noticed another small 'something' that I'm away to methodically check before posting anything about on here, if I'm right, it will be important information for anyone thinking about purchasing either of these two new S&W handguns (29 & 629) and something that I've missed in the review.....oops (*embarrassingly red faced*) Well, not as embarrassing as I thought it would be. I noticed that the shells for the 629 are slightly larger than the standard Colt SAA pellet or BB shells. I've only been using the six shells that I got with the gun since I purchased it (just for the continuity of the various tests I was doing) and when I dropped the standard Colt SAA shells into the cylinder they looked and felt a bit looser. So I measured them and on average they are 1.4-1.5mm thicker than the SAA shells, but the real question is will it make much of a difference ? So I set about trying the 629 shells in all four of my Colt SAAs, they only failed to load in one of them (my Blue Cavalry model) and even then it was just two of the six shells wouldn't go in fully. As some of you may or may not know, I use the SAA shells in my Colt Python, so I tried them in both of those (4" & 6") and they loaded fine, infact they were a lovely snug fit, much better than the standard SAA shell fit them. The 629 shells seem to taper outward slightly towards the base of the shell and that's where they were jamming when I tried them in the SAA that they failed to load in. From the readings on my digital calipers, the standard Colt SAA shells come out as .38" and the 629 shells come in at .40", so they are more like a standard .40 cartridge rather than anything else. As for putting SAA shells in the 629, well the smaller shell's central axis will drop by 0.75mm the line of the barrel as the cylinder rotates, which may or may not cause the pellet to clip the forcing cone as it enters the barrel but if the forcing cone is funnelled out enough (by at least 1mm) then it should theoretically be okay to use the SAA shells in the 629. Would I do it ? hmmm, not sure at the moment, this may be the subject of a further test to see if it effects accuracy and/or power. And before anyone mentions the fact that the barrel states .44 Magnum and the shells are .40 calibre, let's just remember that at the end of the day it only actually fires a tinny weeny .177" pellet out the muzzle when all is said and done, lol.
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