.25 JSB Heavy quick review.

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Michael,
My test using the Labradar over 75 yards indicated BC 0.0 53 to 0.056 using Chairgun and Steve Woodward's calculators respectively taken at the farm at 3,640 ft altitude. Here at home over 20 yards I get 0.05 at about 160 ft above high tide, 

Here is the report I made with the raw data.:

http://www.network54.com/Forum/79537/thread/1433136252

Kind regards, Harry,

 
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No AJS, I bought 10 tins of the Mk 1. I doubt my supplier will import many more than he has already. The market here is not huge.
So it could be some time before the opportunity to try them comes around.
The second 100 yd group I shot with the originals went right on 1/2". I only have single shot rifles so the magazine problem I read of doesn't matter to me. Besides I size all my .25 pellets to 0.2500" which would probably solve the mag problem if I had such.
Best regards on this perfect Spring morning, Harry. 

 
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I managed to get some photo's today. The Mk2 is on the right Mk1 on the left.
Edit: Added measurements below photos.






See what you think.
Ok I got out the digital calipers. I measured 3 of each to get an average.

Original (Mk1) Mk2
inch/mm inch/mm
Head dia: .250/6.35 .250/6.35
Waist dia: .200/5.08 .200/5.08
skirt dia: .262/6.65 .259/6.58
height: .353/8.96 .345/8.76

The mk2's are shorter and the skirt is narrower. I don't have a scale so no weight data.
 
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"30cal"I managed to get some photo's today. I have not had a chance to measure them yet but I will in a day or two. The Mk1 is on the right Mk2 on the left.


See what you think.
Click to expand...
I think you have the positions reversed.
My Mk1s skirts look more like that in the left of your picture, that with the thinner skirt.
Further, Guod 123 described the difference further up as, "... the skirt is noticeably heavier, and the indentation is shallower than the earlier ones". ... Your first pic seems also to show the right hand pellet as being a tad shorter.
But you be the judge there 30 cal. ..... Kind regards, Harry.
 
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Finally got to shoot some MK1 heavies. Velocity dropped from 940 to 800 (as expected). It was pretty gusty & windy but they seemed to group really well. Gonna check out my hammer spring tomorrow to see if I can squeeze out a little more juice. But I think I may be maxed out. Although I'd love to increase the velocity I may lose some accuracy if I push the gun too hard.
 
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Thanks Travels! I used to be a photographer in a past life. I used a Canon DSLR with a 180 mm macro lens with a remote shutter release on a tripod. Pellets sitting in a window box for light.
While I was at it took a pic of a splatted pellet for my avatar photo. Been meaning to do that for a while now. Just needed some motivation to get the camera gear out. Thanks AJ!
 
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"30cal"Thanks Travels! I used to be a photographer in a past life. I used a Canon DSLR with a 180 mm macro lens with a remote shutter release on a tripod. Pellets sitting in a window box for light.
While I was at it took a pic of a splatted pellet for my avatar photo. Been meaning to do that for a while now. Just needed some motivation to get the camera gear out. Thanks AJ!
Click to expand...
I love photography as well and appreciate a good pic when I see one. You should reach out to Pyramyd Air and propose shooting pics of every pellet they sell in the same fashion as the pics above. That would be invaluable to customers. Naturally you should get paid for your services. Just a thought.
 
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"ajshoots"I finally got around to sizing and testing the heavies out of my 2 custom mrods. One is set at 964fps with standard jsb kings. It shot the heavies at 870fps. The other gun is set at 840fps with 43gr eunjins. That gun shot heavies at 915fps.

Both guns have proven equally accurate and the heavies were nearly the same out of both guns even with the speed difference. I only had a chance to shoot out to 75 yards, but both guns shot them to moa accuracy out to 75. Under these same conditions, I would have a hard time shooting to the same level with standard jsb kings in the same wind conditions. It is apparent that the heavies are very good and with a higher BC, they are definitely better in the breeze!! As a note, these are the original heavies sized to .250". Not sure why they made a change as these fit just fine prior to sizing in multiple marauder mags? Hope the new MKII's are as good as the originals!!
Click to expand...
Hi ajshoots,

How did you get your marauder to shoot 964fps with the standard kings. Will a stronger hammer spring (10 pounds ) do the job? With my standard marauder 880 pfs is the max.

Regards,
 
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PCPair, I customize/modify Marauders. The two guns I refered to in the first post of this thread have ALOT of work done to them. Custom valves and hammers is the main ingrediant to this massive power increase. Both guns also have 12.5lbs hammer springs as well as custom transfer ports and modified barrel ports. Not sure if you are located here in the United States or not? If so, here are some links to custom parts that can make your guns shoot like mine.
www.wickedairrifles.com
www.hillairgun.com

Also feel free to PM me as I will be more than glad to give you all the details about my guns and even how to make your gun perform the same.
 
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