I have a 99 coming that has what looks like a Lyman 57SA base mount on it, but the entire upper portion of the sight is not with it (i.e. the scale/screw adjustments, aperture).

Is the upper section of Lyman 57s the same across all Lyman 57s, or would it be specific/unique to a 57SA? Every now and then I've seen an upper section w/o mount on ebay.

thanks, Keith

A conditional "yes". Make sure you get a LH oriented sight slide. 57's aren't as close toleranced as 48's (48's were hand fitted for a perfect fit) but I have encountered them where the parts didn't interchange. Pretty rare for them not to though. Get the correct LH slide and you should be ok.

What Gary said.

Yep, with a 57 you can take a slide off a 57WJS for a Winchester 70 and pop it on an SA. Like Gary said make sure it's a left hand slide, the windage scale on the slide will be on the barrel side of the slide.

Unlike Redfield slides which you can find about four different left hand slides. They moved the elevation stem holes alot during their years of production. Some are forward, some are rear and some are smack in the middle and won't fit just any base like the Lyman 57 will. Also, some later Lyman 57 sights used thinner elevation stems, I have a 57 TS base that a 57 slide won't fit in because the hole for the stem is to small but a Lyman 66 stem will fit it, most likely some transition hick up and they wanted to use up the rest of their bases before switching over to the model 66's.

Glad you mentioned that 57 vs. 66 hiccup, Joe. That scenario tripped me up once too. Same size slides but different stem diameters/threads.

Keith, even if you screw up and end up with a RH slide it'll still work. You will just need a long-shanked aperture to span the width of the cross beam on "the wrong side". Apertures-N-More can fix you up.

Redfields are good sights but too many variations means you can get caught out if you try mixing and matching. That's why I avoid them if I can. I have one on a Mauser that I can't budge the screws on to save my soul. Someone must've used the most tenacious thread locker in the world. So be it, it's a good sight so it can stay there. (And no, I didn't go so far as to apply heat to break them free. It's really not that big a deal.)

I'd like to know if Lyman used the same thread and screw diameter on the 66's as they did on the 56's, that would save alot of headaches.

I notice on the target knob 66's they look really really close to the same target knobs as the 56. I don't have a 66 here to match up to my 56 sights.

Makes sense. I don't have one either with which to make a comparison.

I only have one 57 on a 99, my 99T, and I really like it. I've used 57's on a bunch of other rifles over the years. It's a good serviceable sight. I do opt for 48's when I can, but collectors are driving prices up on them. Average cost for a 48 WJS went up around $100 over just a couple years. Luckily 57's are still mostly reasonable.

Great info. I looked at pics of the one I have on my 99F, I now understand the left/right. Gary, good to know I have an aperture fix, even if I can only find a right.

When looking straight at the elevation scale, on a "left" the windage scale is on the left side (or the muzzle/barrel side of the sight).

It's usually the same guy buying them up and way more than $100.

I sold a 48 WJS to him with an ending bid of $410. Guy has deep pockets and must be a pre-64 70 collector.

Recall reading somewhere that the slide and base were hand fitted on the Lyman’s and were often not interchangeable on the same model sights. In my admittedly limited experience I have found this to be the case on two occasions.

With Lyman 48's your right, the rest are pretty generic.

Brownell has the target windage (539-399-261WB) and elevation (539-399-262WB on back order) screws for the 57 for around $5.