Question about rail/weaver/picatinny on rem. 870 tactical

[Silly Lion]

I'm a big novice when it comes to terminology, so please excuse my vague title. I've recently acquired a remington 870 tactical, and I love it! I'm in the process of customizing it, I've put on a pistol grip so far, but I want to add some attachments. There aren't any holes drilled through it, so I'm wondering if there's a way to add a rail/weaver/picatinny (my apologies, I really don't know the difference between the three) without drilling holes. Is it necessary that I drill holes? If so, can I do it myself, or should I take it to a smith?

Thanks for your help!

[xridgelinerx]

Let's see if I can explain it. Rail is a generic term. Both Picatinny and Weaver are types of rails. This link does a real good job of explaining the very minor differences.

http://www.brownells.com/.aspx/lid=1072 ... ifference_

Bottom line, I think, is if an accessory is made for a Weaver rail it will fit on a Picitinny rail as well. If it is made for a Picitinny rail it may or may not fit on a Weaver.

Another way to think of it is Weaver is for us civilians and Picitinny is the same basic size, but meets the stricter military specifications and tolerances.

As for drilling and tapping the holes, it is up to you. How handy are you and do you have the tools? You want the rail to be dead centered and hold tight. Drilling the holes requires a drill press to get them plumb, straight, and aligned. You aren't going to get this right with your cordless Makita. Tapping requires the proper thread size taps. I'm a pretty handy guy but personally, I would go to a gunsmith.

[Silly Lion]

Thanks for your post, it gave me a lot of clarity about the difference between weaver and picatinny. I'm pretty handy and have a lot of tools, but I'd rather let a gunsmith drill the holes if necessary. Now for the next question, do I need holes drilled, or are there weaver rails that don't require drilling?

[Synchronizor]

There are a number of options for adding rails that don't require tapping your receiver. A popular one is a receiver-mount rail that attaches by replacing the trigger plate pins. These can be receiver-length to full-length, and some have shell carriers built in.




You can also find stocks that have built-in rails of varying lengths.



Another option is the cantilever rail, which is permanantly attached to the barrel, and overhangs the receiver. These are great if you want to have an optic that will always hold its zero relative to the barrel, even if you take the barrel off. However, these only come on fully rifled slug hunting barrels. If you want one of these on a smoothbore barrel, that'll probably be a custom job.

[Automag]

I think you've been shown some good examples of adding a pic rail, which is much more desirable than going with a weaver on a shotgun, unless you plan on just using a scope for some reason. Pic rails accept all manner of addons that are useful for a shotgun, eg. holographic sights, folding battle sights, a rear ghost ring sight and so on. Synchronyzer posted some of the more popular addon pic rail systems. If you go to Amazon, you will see a plethera of addon weaver and pic rail mounts to choose from, many of those i would'nt recommend. Mesa Tactical makes the best sidesaddles and pic rail combinations, actually all Mesa's products are high quality and IMO the best products on the market.

I myself have the Mesa Tactical 5" pic rail and 6 shell sidesaddle combo and have been extremely satisfied with that particular choice. As for drilling/tapping the 4 holes for use with a flat pic rail to mount to, my regualr gunsmith told me he would do it for $80 bucks ($20 bucks a hole) and it would done with the same specifications and placement that Remington uses. I myself, even being a machinist, would rather have a trusted gunsmith handle that job for me.

Heres a older pic of my 870 with the Mesa Tactical 6shell sidesaddle/5" pic rail (which mounts from both sides).