Just acquired a Model 647 with 8 3/8 bbl. and tried it at the range today with both CCI and Hornady ammo, both 17 grain loads. Once I got the gun on the paper at 25 yards, I got good groups with both loads - maybe a little better with the Hornady - but the CCI's grouped about 2" left of the Hornady's which is, or course, easy to fix by adjusting the sights. Anyone have any experience with this revolver? Any advice about ammo? Should I try a heavier bullet weight (granted, a few grains may not matter)?

Interesting. I don't have a handgun in .17HMR, but I do have a Marlin 917V rifle chambered in that caliber, and have found it to be very accurate. I have only used Hornady 17 grain V-Max in it, and have been very pleased. I'm surprised to hear of the drastic difference in point of impact. The rumor is that all .17 HMR is produced by the same facility, on the same equipment, with exactly the same components and loading, just different headstamps and packaging - that certainly doesn't seem to be true, based on your experience between the two brands of ammo.

I recommend trying the various brands and bullet weights, and picking the ammo that seems to be most accurate in your gun.

I also have the 647 and it may be the most accurate gun I own. Both CCI and Hornady shoot great in the gun but mine also seems to like the Hornadys just a bit better. I constanly get groups you can cover with a dime at 30yds.

All .17 HMR ammo is made in the same plant...

Try some 20 gr as well....

Interesting, if all .17 HMR's are made the same, why did Remington recall theirs?

I have the mighty 647 and have recently fit a Burris 2-7x scope to be able to maximize the potential.

Have only had it out once long enough to bore sight and get the group on the bulleye at 25 yards using the 17g red box stuff. Managed to work the group down to a couple inches across before darkness arrived. Will be taking it back to range tomorrow to answer a number of questions.

I have on hand both 17 and 20 grain red & blue box stuff.....PLUS the famed Savage 17whatever model, which DID fire 10 shots into a 1/2 dime size group at 100 yards last summer on a unwindy day using the 20 grainers.

Will be posting more on both soon.

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Here's 40 yard result; 2nd time out with 647-8 3/8" barrel; Burris 2-7 scope.



Best group at lower left 2nd from bottom using 20g blue box; the 20g red box gave decent group on the other side of target but about 2" to the right.

17g of either red or blue box did not group as well as 20g.

EDIT to add: I just noticed you can't see much of the tiny little holes here. Well SOME of the bulls were not used as time was limited. I don't know how to increase image size here.

My lowest target paper was for the 20g blue; the upper for the 17g blue & red; the middle was for 'mixed' didn't write it down. Sorry for the bum photo.

I expect considerable improvement with a little more practice....and cataract surgery is pending (excuse 1)

"I just washed my gun and can't do a thing with it " (excuse 2)

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