New 870 Police Magnum first range day
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New 870 Police Magnum first range day
I recently purchase an 870 Police Magnum, with an 18” barrel and tritium rifle sights. I took it shooting for the first time, yesterday November 5th. Gun shot great and felt really nice to use, as 870s usually are. The sights were great when I fed slugs into the mag tube. However, one thing is didn’t know until I shot it for the first time, was the mag capacity. I was under the impression that It held 5+1 rounds, but later found that it was 4+1. At first I thought I wasn’t pushing the last shell into the tube hard enough, but I felt that after 4 shells, it was full. Do you guys think 4+1 is good enough? Or should I upgrade with a mag extension? It was a bit annoying having to reload after 5 shells, but didn’t make love the gun any less.
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Re: New 870 Police Magnum first range day
If i was going to add an extention I would go with a two round extention.
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Re: New 870 Police Magnum first range day
I’m considering it at the moment. A Wilson Combat +1 extention is what I have in mind, but still not sure.
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Re: New 870 Police Magnum first range day
4+1 is the standard capacity for an 870 without a mag extension or a nonstandard long tube. You can get 5+1 with some simple tweaks and shorter 2.5" or 2.25" shells; but with normal 2.75" shells, you're going to need an extension if you want more than four in the tube.
With an 18/18.5" barrel (yours is likely 18.5" if it's a new gun), the "matching" (best lines up with the barrel's length) extension would be a +2, which gets you 6+1. Some +2s are more space-efficient than others though, and if you combine a roomy +2 tube with the right spring & follower, you can get it to hold three extra 2.75" shells, for a total capacity of 7+1. The newer S&J Hardware +2 kit is one that'll do this out of the box, but there are other extensions that can also manage it with some fiddling.
Keep in mind though, that the more you add to your gun's mag tube capacity, the more weight you'll add from the tube, any reinforcing clamp, and of course the shells themselves; and the more nose-heavy the gun will become. This is where a +1 extension can be a nice compromise between capacity and handling. +1s also tend to be simpler and easier to make reliable than longer extensions, since they're basically a stretched magazine cap, and are mostly just there to make room for the spring.

With an 18/18.5" barrel (yours is likely 18.5" if it's a new gun), the "matching" (best lines up with the barrel's length) extension would be a +2, which gets you 6+1. Some +2s are more space-efficient than others though, and if you combine a roomy +2 tube with the right spring & follower, you can get it to hold three extra 2.75" shells, for a total capacity of 7+1. The newer S&J Hardware +2 kit is one that'll do this out of the box, but there are other extensions that can also manage it with some fiddling.
Keep in mind though, that the more you add to your gun's mag tube capacity, the more weight you'll add from the tube, any reinforcing clamp, and of course the shells themselves; and the more nose-heavy the gun will become. This is where a +1 extension can be a nice compromise between capacity and handling. +1s also tend to be simpler and easier to make reliable than longer extensions, since they're basically a stretched magazine cap, and are mostly just there to make room for the spring.
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Re: New 870 Police Magnum first range day
Ah ok. Many thanks for clearing that up. I tend to prefer less weight in terms of ammo capacity, so the 4+1 mag capacity could be good for me, but that may change. I have yet to measure the length of the barrel, as the box label says “18”, while I have heard that It might actually be 18.5”.Synchronizor wrote: ↑Tue Nov 07, 2017 8:21 pm 4+1 is the standard capacity for an 870 without a mag extension or a nonstandard long tube. You can get 5+1 with some simple tweaks and shorter 2.5" or 2.25" shells; but with normal 2.75" shells, you're going to need an extension if you want more than four in the tube.
With an 18/18.5" barrel (yours is likely 18.5" if it's a new gun), the "matching" (best lines up with the barrel's length) extension would be a +2, which gets you 6+1. Some +2s are more space-efficient than others though, and if you combine a roomy +2 tube with the right spring & follower, you can get it to hold three extra 2.75" shells, for a total capacity of 7+1. The newer S&J Hardware +2 kit is one that'll do this out of the box, but there are other extensions that can also manage it with some fiddling.
Keep in mind though, that the more you add to your gun's mag tube capacity, the more weight you'll add from the tube, any reinforcing clamp, and of course the shells themselves; and the more nose-heavy the gun will become. This is where a +1 extension can be a nice compromise between capacity and handling. +1s also tend to be simpler and easier to make reliable than longer extensions, since they're basically a stretched magazine cap, and are mostly just there to make room for the spring.
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“Civil Wars happen when the victimized are armed. Genocide happens when they are not.”
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Re: New 870 Police Magnum first range day
After racking my brain over what to do, I decided to order +1 shot extension from Wilson Combat. I figured it’s better to get that extra round, making it 5+1. Can’t wait to get it and install it! Thank you so much for the valuable insight and advice!ShotgunSam870 wrote: ↑Wed Nov 08, 2017 1:36 amAh ok. Many thanks for clearing that up. I tend to prefer less weight in terms of ammo capacity, so the 4+1 mag capacity could be good for me, but that may change. I have yet to measure the length of the barrel, as the box label says “18”, while I have heard that It might actually be 18.5”.Synchronizor wrote: ↑Tue Nov 07, 2017 8:21 pm 4+1 is the standard capacity for an 870 without a mag extension or a nonstandard long tube. You can get 5+1 with some simple tweaks and shorter 2.5" or 2.25" shells; but with normal 2.75" shells, you're going to need an extension if you want more than four in the tube.
With an 18/18.5" barrel (yours is likely 18.5" if it's a new gun), the "matching" (best lines up with the barrel's length) extension would be a +2, which gets you 6+1. Some +2s are more space-efficient than others though, and if you combine a roomy +2 tube with the right spring & follower, you can get it to hold three extra 2.75" shells, for a total capacity of 7+1. The newer S&J Hardware +2 kit is one that'll do this out of the box, but there are other extensions that can also manage it with some fiddling.
Keep in mind though, that the more you add to your gun's mag tube capacity, the more weight you'll add from the tube, any reinforcing clamp, and of course the shells themselves; and the more nose-heavy the gun will become. This is where a +1 extension can be a nice compromise between capacity and handling. +1s also tend to be simpler and easier to make reliable than longer extensions, since they're basically a stretched magazine cap, and are mostly just there to make room for the spring.
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“Civil Wars happen when the victimized are armed. Genocide happens when they are not.”
― A.E. Samaan
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Re: New 870 Police Magnum first range day
Just curious is that stocked numbered because it was a police weapon?Synchronizor wrote: ↑Tue Nov 07, 2017 8:21 pm 4+1 is the standard capacity for an 870 without a mag extension or a nonstandard long tube. You can get 5+1 with some simple tweaks and shorter 2.5" or 2.25" shells; but with normal 2.75" shells, you're going to need an extension if you want more than four in the tube.
With an 18/18.5" barrel (yours is likely 18.5" if it's a new gun), the "matching" (best lines up with the barrel's length) extension would be a +2, which gets you 6+1. Some +2s are more space-efficient than others though, and if you combine a roomy +2 tube with the right spring & follower, you can get it to hold three extra 2.75" shells, for a total capacity of 7+1. The newer S&J Hardware +2 kit is one that'll do this out of the box, but there are other extensions that can also manage it with some fiddling.
Keep in mind though, that the more you add to your gun's mag tube capacity, the more weight you'll add from the tube, any reinforcing clamp, and of course the shells themselves; and the more nose-heavy the gun will become. This is where a +1 extension can be a nice compromise between capacity and handling. +1s also tend to be simpler and easier to make reliable than longer extensions, since they're basically a stretched magazine cap, and are mostly just there to make room for the spring.
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Re: New 870 Police Magnum first range day
The furniture is an old take-off set from a police armory shotgun. The gun itself is a pretty standard #20577 Express from before Remington switched that model over to the long single-piece 6-round mag tube.