I’m building a slug gun for hunting deer in brush where shots run from 30 to 100 yards. It’s based on an 870 Express with an 18" cylinder-choke barrel and Scattergun Technologies Trak Lok II night sights. I test-fired it today, and it hits +5" at 50 yards even with the rear sight bottomed out.
The S&B Special Slug 28 load is accurate in this gun and doesn’t kick hard at all. S&B claims it’s doing about 1,350 fps. I also tried Federal’s 2 3/4" Magnum load, which is accurate and kicks like a bastard. Both loads shoot about the same size groups in the same place.
In a perfect world, this gun would hit dead on or a bit high at 50 yards and the rear sight would not be at the limit of adjustment.
If your running Sabot loads in a smooth barrel , that may be your problem, if you can find them try a couple of 5 packs of the older slug loads like the Bernneke{sp}
I’ve installed a couple of ghostrings from Wilson/SGT - if you measured correctly I don’t see how the rear sight could be mounted too high on the receiver - it has a slight ‘curve’ is it in full contact?
How did it shoot with the bead before mounting the sights?
Barrel fully seated and mag tube end cap snug?
I’d suggest is letting someone else shoot it just to be sure.
If it is indeed off and you are patient and careful and make very small adjustments, I’ve used the receiver of a receiver hitch to gently torque the mag tube to lower point of impact for bead sights - I generally make sure there are no witnesses to this operation. - never seen a Ghost Ring that couldn’t be adjusted enough - but I certainly have not seen them all.
“I’ve used the receiver of a receiver hitch to gently torque the mag tube to lower point of impact for bead sights - I generally make sure there are no witnesses to this operation”
About 40 years ago I had a 22 rifle adjusted by the local smith. He used a tree behind his shop for the operation. I would have rather not seen it done but it worked! GH
I have that exact set up, reading through the thread you already mentioned what I thought it was “mounted to high on rear”. Not having mounted the sights my self I don’t even know how to measure it. I would do as suggested and call Wilson Combat, If they did have a taller front which I doubt they do I do not envy the work you have in-store to get that epoxy off.
If it had to come off and be moved down and you don’t have a tig welder, make dam sure you get some one who knows what their doing to fill in the old holes after you fill them with screws!
Thanks for your answer. The barrel is fully seated and the cap is snug.
I didn’t shoot it with just the bead. I bought the gun as a combo (bird barrel + 20" deer barrel). The POI of the 20" barrel was fine with the stock Remington rifle sights. Then I had the SGT ghost ring installed, and the gun started to hit too high with the factory front sight, which is the exact same height as the SGT blade. I swapped that barrel to a member here for the 18" smoothbore barrel, added the SGT front sight myself, and the high POI is still there. I’m fairly certain that the sights themselves are in spec, and that I’m shooting it well enough, since the groups are about like they were with the factory sights.
I think the issue(s) are that either A) the rear sight was installed too far forward and is thus too high, B) since POI isn’t that far off and we’re talking an 870 that’s basically a parts gun, tolerance stacking could be a factor, or C) both.
I’m hesitant to take the gun back to the guy who drilled the holes for the rear sight, since if he couldn’t get it right the first time, then I don’t have much hope that he’ll get the correction right, either.
Care to talk me through the receiver hitch method? Feel free to PM me if it’s too gory for the public.
I had a similar experience where the “gunsmith” that I took the gun to didn’t follow the directions, even though I specifically told him that I wouldn’t be able to zero the gun if he didn’t. He didn’t and 25 yards is the farthest I can zero that gun with slugs.
WC/SGT does have different height front sights. If you bought the tall front sight (the one for 14" barrels), it might work. That is a lot of work for a maybe though.
“Care to talk me through the receiver hitch method”
26INF put the mag tube into the hitch receiver and bent it slightly. I worked for him but I would bend the barrel before the tube, Bending the tube will impact the poi of every barrel you have. Get the directions from ST, remove the rear sight and see if your smith drilled the holes in the wrong place. If he did it may be easier to raise the front sight assuming he didn’t pin it to the sight base. GH
You are moving the mag tube up or down - I’ve done it in the field by placing the tube (wrapped in a rag) in the receiver hitch and using a babbit to strike the union of the tube and receiver - gently. I’ve also done it on the bench with a dent expander in the mag tube to prevent the tube from deforming. It requires patience - each tap requires a shot to see what you’ve done.
As noted this will change POI with other barrels.
Over the years I’ve seen police 870’s with beads mounted directly to the barrel and with beads mounted on a ‘pedestal’ - swapping barrels amongst guns makes a difference in POI. As a result we stamp receivers and barrel rings with numbers to make sure they remain matched up when we mass clean shotguns.
Since yours is a parts gun this may have happened.
Center and level receiver in drill press or milling machine vise.
Measure and mark rear sight holes. NOTE: Front hole mark should be 5.885” and rear hole mark 7.335”, both indicated from front of receiver. The hole spacing is 1.450”
Use #33 drill to drill front hole through receiver and rear hole .375” deep.
Use 6/40 tap to thread both holes.
Mount rear sight using screws and wrench supplied. NOTE: Snug down screws only. Do not over tighten.
I used a drill press in our maintenance shop to do this - it isn’t that hard, the base of the sight is ‘curved’ to match the receiver so if you’ve got it high enough to run out of adjustment, you should be able to see it is out of place when loking from the side.
It does look as though Wilson sells three different sets, one for regular (18 - 20?) barrels, one for 14 inch - .735" and one for 12.5 inch - .785"
- never seen a Ghost Ring that couldn’t be adjusted enough - but I certainly have not seen them all.