[ am trying to decide betwees the XS ghost ring, Skinner sight, and the Williams FP or WGRS (if it doesn't hang over the back of the receiver on a 336 like it does on the 1894 - still cant find an answer to that).]
The WGRS does not overhang the rear/hammer of a Model 336.
[I am leaning toward the XS because its not as bulky as some of the others but I like how I can use multiple apertures for the other sights while the XS only comes with 2, and they are larger than most of the other offerings - will that affect accuracy?
1) Upon request, the XS Ghost Ring peep is available with an aperture stem that's threaded to take removeable apertures, just like any other peep sight.
2) Aperture size effects both accuracy and speed/handiness, but in opposite directions:
The smaller the aperture, the tighter the accuracy but the slower to acquire/use on sudden/game shots.
The larger the aperture, the looser the accuracy (only slightly) but the speed of acquisition increases dramatically.
Many seasoned users, in fact, zero/practice with a small aperture, then entirely remove it and shoot/hunt using the resultant ghost ring.
[The Williams FP is pretty bulky and not my favorite in the looks dept but do seem very functional
You might also want to consider the Williams 5D - which is similar to the FP, but at half the $$$$, due to no micrometer adjustable w/e.
The 5D, XS and Skinner are all "set 'n forget" sights, best used by a one-load shooter - since they're not readily re-adjustable for repeated changes in the field or in a target game like silly-wets.
The FP is better for frequent changes in zero.
ALL the top-mount peeps will require a commensurately higher than issue front sight blade, since they each raise the issue line-of-sight by at least 1/10".
Many take the opportunity to change front sight type to a different material they like better, beit gold bead/ivory bead/ fiber optic bead.
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