[Basrem]

I have shoot Winchester ammo for a long time Super X was my go to ammo (Daynapoint's back in the 90's) in my T 10/22. Now I have a 597 and it will only shoot CCI SV if I want good groups. all other ammo will go under an inch or more,( OPEN UP) depends on the ammo at 50 yds CCI SV right at 1/2 to 3/4 at 50 yd's. Now My MKIII will shoot CCI SV and Winchester 555 bulk just about then same just thought it was one of those things you know one day you can not do wrong shooting. Well went to the farm It has beed 12 weeks sence I have shot any thing, I was grouping better with the win 555 then CCI but I do think IT'S the lot's of winchester because some times a bulk box will not group for S&*@, CCI SV will stay the same brick after brick, just my 2 cents

 

[ejhc11]

I like the Winchester M-22s more, the bullet is rounder and feed 100%. The 555s have a slight truncated shape that will FTF every 20 rounds in my dedicated 22LR AR upper. Both are pretty clean, the powder charge and groups are very identical.

Oh, the AR uppers actually group tighter w/the dreaded Remington GBs than CCIs, go figure. And, they don't have any FTF or FTEs either w/GBs.

 

[SMU Aggie]

I have had horrid results with the Winchester 555 in my Remington 597. But ammo from the same box was grouping great in my grandad's old J.C. Higgins model 30. Go figure.

 

[ivan]

I've only used the 555 in my GSG 1911-22, and it works great with it...

 

[Busyhands94]

I have shot Winchester 555, I got a brick of it a month or so ago and have been nibbling at it with my J.C. Higgins single shot. Here's the one I've got:

Nothing beats having a single shot rifle and a big, fat brick of ammo to last you all day! It may be kinda cheap but it shoots great and I have had no problems whatsoever with this ammo in any of my .22s.

Levi

 

[Wrench Man]

We've burned threw a couple of boxes of the 333 (same as the 555) figure about 1% FTF's?, my 39A really likes them, my 9422 does well with them also our Marlin 25's also seem to like them, don't recall how the Henry did with them?, haven't put and down the tubes of the Marlin 60's so I can't say how the cycle an auto?, all of them I've shot are in the red box, I've heard the new white boxed ones aren't as good?

 

[bigfatdave]

Win555 is the backup option if Fed550 isn't available.

I've reliability tested both (and Rem550 Golden Boogers) and they have similar rates of failure (5-6 per box don't fire on first try, 2-3 of those don't fire on three tries, less than "one per box" incidence of a completely mis-shaped round. Those numbers were signifigantly higher for Rem550GB, around triple, if I remember right)
Of course, my testing method doesn't account for all the bad primers that aren't in the portion of the rim crimped by the FP, so who knows how many priming gaps there really are. I also failed to actually count rounds, I was just marking on the box-top flap with a sharpie and realized AFTER two bulk packs of each that I should have figured out if the advertised number were in the box, I doubt it is exact but I'd bet there's extra in any given box, much like the loose 9x19mm 100-round packs from Winchester (generally 101 or 102)