I attempted to find the answer to my question on a different thread but came up empty.
Owners: How accurate is your 648?
What ammo have you tried?
Thank you.

__________________
Tennessee

It's been awhile since I shot it so don't remember what ammo I last used. Don't remember that anything I fed it was a problem. This one, obviously, has had a bit of finish work. Can't imagine that you wouldn't be happy with accuracy of any of them. Good luck.

Jeff
SWCA #1457

Attached Images

648 22 Mag with Leupold 2X.jpg (46.4 KB, 105 views)

30 gr. Hornady. Less than one inch at 25yds about 23/4 inches at 75 yds.All groups were shot off of rest with a Leupold pistol scope 2 1/2 X 8. Only fired 50 rounds so far. No problem with ejected cases or excessive carbon.

I don't have any notes written down, but my 648 so far has only had what I would call decent groups at 25 and 50 yards using Winchester ammo. More FMJ than WW HPs. CCI was terrible. Federal not much better. Can't remember about Remington or Hornady, except that Winchester was noticeably better. Currently I have a bit over an ammo can full of WW .22 mag ammo (mixed lots, some FMJ, others HP), and haven't thought to try anything new lately. Aguila, for instance.
It's not a primary small game revolver, as my 8 3/8" 617 goes afield 95% of the time. But it is kinda fun! Especially now that .22 mag ammo prices have moderated considerably.

I had the same accuracy issues with my 648. I changed sights, and used several different ammos, with limited success. Some ammo was very dirty and required constant cleaning during a shoot, but I can't remember which were worse. I posed the same question here several years ago. With no real solutions either.
This thread got me thinking so I took mine out again after a couple of years and was pleasantly surprised with the accuracy. However, it still has more fliers than I like. I was shooting offhand at 20-25 yards. The more I shot, the worse the groups were so I figure I was getting lazy and losing my concentration.
It was CCI ammo and worked very well in my Henry Golden Boy during the same shoot.
I'll take the 648 out again and bench it at 15 yards with CCI and Federal ammo to see how it shoots. When the weather moderates a bit.

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Witzell
"The dude abides".

Finally got a look at the 648 and found that Armscor .22 mag ammo was found to be second only to WW in accuracy. Got the hankering to try it some more after this thread. Barrel's kinda short, but I keep hoping it would do for Field Pistol. (1/2 scale Rams at 100yds, standing, might be the big challenge to knock over. Power wise, otherwise it's the evil "dancing" tiny 75 yd Turkeys that will give fits)!

I have wondered the same thing. Last week I benched 4 different ammos at 10 yards and found the scores to be pretty much the same. BUT, there were some flyers with each ammo leading me to think there was an issue with the gun. Before I thought it was my 71 year old eyes. Maybe I should check the timing...... or live with it.

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Witzell
"The dude abides".

Gunsmith said my 648 has timing issues.he seems to think he can fix it with no major issues....

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Witzell
"The dude abides".

Gunsmith finished working on gun, but I haven't been able to check it out yet. The range is closed due to virus..... maybe it take it out into the desert and try it out.

__________________
Witzell
"The dude abides".

S&W 648 reduced.jpg
S&W 648:
25 yards with a scope and CCI I can reliably hit bottle tops set on golf tees.
Aguila 22Mag ammo is really hot, topping 1850fps from my S&W 648 with 6" barrel. It seems to group a little larger than the CCI. Sometimes didn't hit the bottle cap on the first try.

The 648 has been completely reliable, though I haven't fired more than about 500 rounds through it due to the cost of ammo.