Scope mounts Rem 870 20 gauge

filmjunkie4ever

Handloader
May 4, 2011
1,913
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Who here hunts with a shotgun? Its something I’ve always wanted to try. I see all kinds of mounts out there and am not sure which one to use.

My shotgun is a Remington 870 20 gauge with the 28” smoothbore barrel. I will be using rifled or brenneke slugs.

Not sure if I will use a red dot or holo sight, or just use a scope. But if you guys could steer me towards a quality weaver saddle mount, that would be great!
 
If I'm not mistaken, I have a B Square saddle mount for an 870 12 ga. The two trigger pins are replaced with machine screws. I've got a red dot for turkey hunting. Holds it's zero even after removing and reinstalling the mount.

JD338
 
I had my Benelli SBE receiver drilled and tapped . I mounted a picatinny rail on it . I use an EOtech holo sight on it . I did this just before Burris came out with the speedbead sight . if I had waited a little longer I'd probably went this route .




edit to add ;
I didn't think I had a pic of it .

PC300269.JPG
 
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OK- here's my whole sermon- In 35 years of trying to get slugs to shoot like my 250 Savage, I've developed some opinions- keep in mind they are just that based on 100's and hundreds of slugs down range in 12, 16, and 20 ga. I offer not because I know it all but to hopefully save you some aggravation. Its what I think I know. First off- I've seen an 870 with a saddle mount shoot a clover leaf group at 50 yards. That one had a rifled barrel as I recall.
One thing you are up against with your 870 is its a "bird gun". As such, the theory is that the barrel floats or resonates to a different point after each shot. It isnt threaded to the receiver like an Ithica Deerslayer, or a Savage bolt action slug gun. I think its harder to keep your point of impact and point of sight in the same spot from shot to shot.

IMHO Saddle mounts add another potential set of movement points. No matter how well they are machined, there are always tolerances. More chances for screws/ mounts to loosen etc. I have a Weaver saddle mount for a Mossberg 500 laying on the shelf. For a dot sight for running rabbits inside 50 yards it might be just the ticket. Too cheap looking for me to waste expensive slugs at 100 yards with that. I watched a guy beat himself up with multiple slugs using a saddle mount on a Rem. auto. . Very eratic groups, so we start checking screws etc. We got the screws to hold things still enough to shoot a reasonable group, but his 1100 stopped repeating until we loosened the screws on the saddle mount. I dont want to have to rely on a "happy medium" screw tension to get a "passable group.

Another difference- the accurate slug guns Ive seen have heavier barrels that your 870 field gun. The Ithica I mentioned has a ridiculous looking barrel that is heavy enough to be at home in a prairie dog town. The H&R single shot is the same way. Savage bolt guns are pretty stiff too. Whether the actual stiffness is a factor or the weight are a bigger factor is a debatable question. Personally I think both help. More about recoil later.... Shot gun barrels are not standardized diameters like rifle calibres, they have different internal dimensions so in theroy some barrels will shoot better with a particular brand of slug. As you've lkely already heard, experiment until you find one your gun likes. My 16 Ga will throw federal slugs in a basketball sized group at 50 yards and key hole Remingtons at that distance . Brenekes are the only thing I can make shoot decent in that. Impossible to find these days. 8.5 pound trigger pull dosent help either..... super light cylinder choked barrel, Kicks like an Angus. No fun to shoot, nice to carry.
I would suggest trying Federal "tru- ball slugs. They are comparatively cheap, available, and have shot reasonably well or better in several guns Ive seen. My father in law can plug a a 6in. plate at 100 yards fairly consistently, with a mossberg 500 Cylinder bore.

Chokes - He used to use an old Remmington Model 11. (Browning A5 copy). That one would reportedly shoot Rotweil slugs accurately through its full choke. Never saw it done. In his 80's the mossberg is easier to carry.... he shot his deer with the Mossberg (Cylinder choke and Tru -ball slugs) again this year. Opinions are out there about rifled chokes, or one size better than another... for the sake of your 870 I'd start with the most open choke I could use.

Recoil- allegedly - the barrel of a shotgun moves from recoil before the slug makes it out of the barrel potentially changing the point of impact. My "informal testing" finds this to be at least a possibility. If I shoot my Mossberg off sand bags and let it "free recoil" I am three inches high and left (If I remember correcrtly). Heavier barrels may help limit this. You gotta have a grip on my shot gun forearm. Also just like any other firearm, recoil makes me have bad habbits. My .02, pace yourself. If you shoot a few sugs , use a pad, or cheater and some hearing protection. Then go back to shooting your scoped .22 for a while. Its hard enough to shoot slugs well. If your brain is subconsciously screaming "Oh no- here it comes again!" you wont be happy with your results. In my experience shoot slugs takes experimentation.


All those potential problems aside, a friend of mine helped a young lady "sight in" her smooth bore 20 ga. field barreled shotgun at a public sight in several years ago. With his good coaching, she learned to "stack" the the mid rib an end of barrel beads in her sight picture to get her point of impact right at 50 yards. She was shooting nice 2-3 inch groups by the time she left, proudly taking the target home. I believe she got her first deer that fall with that set up. It can be done, Rifled slugs are cheap, if you find the one your 870 likes, you can do a lot of hunting.
I've seen B-Square and weaver saddle mounts. Also Ive had a 20 ga drilled and tapped. With flat top receivers that's not to big of a deal either. Use the best stuff you can find, limit your expectations, cloverleafs at 100 yards are possible, not the norm. On that front, save yourself some time money and aggravation- do your shooting/ testing at 50 yards. Again, IMHO there are so many variables in "slug shooting" including they just arent as consistent as your reloads. Get it dialed in, then stretch it out and see how it goes. Have fun! And thanks for tolerating my long winded reply. CL

16,12,20
 

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If I'm not mistaken, I have a B Square saddle mount for an 870 12 ga. The two trigger pins are replaced with machine screws. I've got a red dot for turkey hunting. Holds it's zero even after removing and reinstalling the mount.

JD338
I have the same for an 870 20. Works just fine.
 
Glad you guys are having good luck with your 870's and Saddle Mounts. Maybe I shoulda just kept my mouth shut...after all, I dont run an 870. CL
 
Glad you guys are having good luck with your 870's and Saddle Mounts. Maybe I shoulda just kept my mouth shut...after all, I dont run an 870. CL
Actually, I was in error - my B-Square is a rail mount for an optic, not a saddle mount. I apologize to all for the factual error.

Oh, also, I purchased it many years ago and noticed that at the time, QC was not the best. From that experience, I would not suggest anyone buy one online; get eyes on before putting money down.
 
Myself, unless it's a shotgun with a rifled barrel (which I've never owned) I don't think I'd want a scope or any kind of optic on a shotgun.

I do like a good ghost ring sight setup though... works well enough for me at any range a Foster or Brenneke slug is useful for... and no batteries, smudged lenses, or sun at the wrong angle issues (glare).

I should add... I'm not knocking rifled shotguns, just never have owned one.

To be honest, until a few weeks ago I had VERY little experience or interest in buckshot or slugs for hunting.... since getting the Mossberg and playing with some slugs though I'm pretty sold on it for a thick woods deer gun.

The ghost ring sights put Winchester 1oz Foster slugs into nice groups at 50 yards (1.5 to 2 inches)...I'd have no reservations about 75 yard deer with it.

All that said.... if I was going to mount a scope I believe is get it drilled and tapped and put a rail on it... I'm not sure how complicated that is on an 870.... even for a ghost ring, drilled and tapped with a rail is the way to go if at all possible.
 
OK- here's my whole sermon- In 35 years of trying to get slugs to shoot like my 250 Savage, I've developed some opinions- keep in mind they are just that based on 100's and hundreds of slugs down range in 12, 16, and 20 ga. I offer not because I know it all but to hopefully save you some aggravation. Its what I think I know. First off- I've seen an 870 with a saddle mount shoot a clover leaf group at 50 yards. That one had a rifled barrel as I recall.
One thing you are up against with your 870 is its a "bird gun". As such, the theory is that the barrel floats or resonates to a different point after each shot. It isnt threaded to the receiver like an Ithica Deerslayer, or a Savage bolt action slug gun. I think its harder to keep your point of impact and point of sight in the same spot from shot to shot.

IMHO Saddle mounts add another potential set of movement points. No matter how well they are machined, there are always tolerances. More chances for screws/ mounts to loosen etc. I have a Weaver saddle mount for a Mossberg 500 laying on the shelf. For a dot sight for running rabbits inside 50 yards it might be just the ticket. Too cheap looking for me to waste expensive slugs at 100 yards with that. I watched a guy beat himself up with multiple slugs using a saddle mount on a Rem. auto. . Very eratic groups, so we start checking screws etc. We got the screws to hold things still enough to shoot a reasonable group, but his 1100 stopped repeating until we loosened the screws on the saddle mount. I dont want to have to rely on a "happy medium" screw tension to get a "passable group.

Another difference- the accurate slug guns Ive seen have heavier barrels that your 870 field gun. The Ithica I mentioned has a ridiculous looking barrel that is heavy enough to be at home in a prairie dog town. The H&R single shot is the same way. Savage bolt guns are pretty stiff too. Whether the actual stiffness is a factor or the weight are a bigger factor is a debatable question. Personally I think both help. More about recoil later.... Shot gun barrels are not standardized diameters like rifle calibres, they have different internal dimensions so in theroy some barrels will shoot better with a particular brand of slug. As you've lkely already heard, experiment until you find one your gun likes. My 16 Ga will throw federal slugs in a basketball sized group at 50 yards and key hole Remingtons at that distance . Brenekes are the only thing I can make shoot decent in that. Impossible to find these days. 8.5 pound trigger pull dosent help either..... super light cylinder choked barrel, Kicks like an Angus. No fun to shoot, nice to carry.
I would suggest trying Federal "tru- ball slugs. They are comparatively cheap, available, and have shot reasonably well or better in several guns Ive seen. My father in law can plug a a 6in. plate at 100 yards fairly consistently, with a mossberg 500 Cylinder bore.

Chokes - He used to use an old Remmington Model 11. (Browning A5 copy). That one would reportedly shoot Rotweil slugs accurately through its full choke. Never saw it done. In his 80's the mossberg is easier to carry.... he shot his deer with the Mossberg (Cylinder choke and Tru -ball slugs) again this year. Opinions are out there about rifled chokes, or one size better than another... for the sake of your 870 I'd start with the most open choke I could use.

Recoil- allegedly - the barrel of a shotgun moves from recoil before the slug makes it out of the barrel potentially changing the point of impact. My "informal testing" finds this to be at least a possibility. If I shoot my Mossberg off sand bags and let it "free recoil" I am three inches high and left (If I remember correcrtly). Heavier barrels may help limit this. You gotta have a grip on my shot gun forearm. Also just like any other firearm, recoil makes me have bad habbits. My .02, pace yourself. If you shoot a few sugs , use a pad, or cheater and some hearing protection. Then go back to shooting your scoped .22 for a while. Its hard enough to shoot slugs well. If your brain is subconsciously screaming "Oh no- here it comes again!" you wont be happy with your results. In my experience shoot slugs takes experimentation.


All those potential problems aside, a friend of mine helped a young lady "sight in" her smooth bore 20 ga. field barreled shotgun at a public sight in several years ago. With his good coaching, she learned to "stack" the the mid rib an end of barrel beads in her sight picture to get her point of impact right at 50 yards. She was shooting nice 2-3 inch groups by the time she left, proudly taking the target home. I believe she got her first deer that fall with that set up. It can be done, Rifled slugs are cheap, if you find the one your 870 likes, you can do a lot of hunting.
I've seen B-Square and weaver saddle mounts. Also Ive had a 20 ga drilled and tapped. With flat top receivers that's not to big of a deal either. Use the best stuff you can find, limit your expectations, cloverleafs at 100 yards are possible, not the norm. On that front, save yourself some time money and aggravation- do your shooting/ testing at 50 yards. Again, IMHO there are so many variables in "slug shooting" including they just arent as consistent as your reloads. Get it dialed in, then stretch it out and see how it goes. Have fun! And thanks for tolerating my long winded reply. CL

16,12,20
I grew up in an area where we had to hunt deer with shotgun slugs. My experience pretty much duplicates what Troy said. For smooth bores, just try every slug made. You may find one that works well for you. It is just a case of trial and error. My brother actually had the barrel on a model 12 "bent" by a gunsmith to put the P.O.I. of one brand of slug on the bull at 65 yards.

We didn't use scopes until the rifled barrels became available. I had some success with Remington barrels with the extended scope base mounted on the barrel. Also had success with the Ithaca model 87 Deer Slayer II's with the non-removable barrels.

Troy, I have boxes and boxes of 12 gauge Brenneke slugs of various designs (and other brands) that I don't need anymore. PM me if you might be interested in them. Dan
 
Dan- thanks for thinking of me. Truth to be told I have found "the" slug for my Mossberg (Federal-Trophy Copper's) so as far as slugs go I am good. The last several years I have fired one shot a year to confirm my zero and that's been it. Please share your generous offer with some one who is still searching....Besides, shipping would be expensive! :) Some body out there probably has an old 12 that needs a those Breneke's! CL
 
CL has obviously put a lot more thought and effort into this idea. I've never shot a scoped shotgun, and as I don't hunt areas where they're required for deer, I might not ever shoot one. The only reason I might look into one is if I start turkey hunting, which I don't have any plans to do. My concern is that every pump shotgun and most autos I've handled have enough play in the barrel/receiver joint that I can't help worrying about your zero shifting every time you take your barrel off. I would think an optic mounted to a vent rib would work better at maintaining POI. But then I worry about damaging the rib.

Wait, you CAN shoot something other than 3" or 3.5" turkey loads?
 
I have a Rem 870 Tactical that is fitted with the Ghost Ring and front sight.
For bear watch work, it only gets used with slugs. The Federal 2 3/4" and 3" slugs print decent groups at 50 yards (under 2"), so I haven't tried anything else. I won't be shooting at that range in a bear defense situation, unless it is a wounded bear and I am making follow up shots, so this level of accuracy is fine for me.
I also picked up the Leupold Delta Point Pro red dot for it, along with the Leupold base for mounting it, but haven't gotten around to mounting it as yet. Should, so I can experience it first hand, and have it sighted in, should I ever decide to hunt with it. Or need to assist someone in following up on a wounded bear...
 
Who here hunts with a shotgun? Its something I’ve always wanted to try. I see all kinds of mounts out there and am not sure which one to use.

My shotgun is a Remington 870 20 gauge with the 28” smoothbore barrel. I will be using rifled or brenneke slugs.

Not sure if I will use a red dot or holo sight, or just use a scope. But if you guys could steer me towards a quality weaver saddle mount, that would be great!
For sluggos I,d mount a low power variable.
 
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