Does anyone have experience installing these?

[Rocco Stag]

Fellows,


I'm willing to install a LPA/PSI SG set (please check the attachment, disregarding the rail) on my trusty vintage Remington 870 Police, but since I don't have access to a gunsmith I must do it myself - and therein lies the catch.

The first problem is that the front bead is actually a brazed-on, silver-soldered bead-on-a-pedestal. I'd rather not apply heat to the barrel in order to save as much of the original finish as possible. So here are my first two questions:

1) Would a dremel attack suffice to remove it? What pitfalls should I be aware of? Excessive heat, tool bit quirks, or...?

2) When actually installing the replacement FSA, what grade of loctite (or similar adhesive) should I use for a permanent setup?


Second, I must drill and tap the receiver for the RSA, which takes three separate holes. Keeping in mind that all this is a shade tree mechanic WECSOG effort, I ask you what approach should I take to:

1) Make sure that the holes are squared to each other and centered on the receiver;

2) Keep their depth to an even 5mm with simple powertoools and no fancy machinist aids;

3) Tap them to spec as per the M4 screws from the kit;


Thanks in advance to all that comment and/or offer criticism. Your opinions will be greatly appreciated!

Regards,

Rocco

 

[dfariswheel]

The best way to remove the Remington ramp is to cut it off.
I'd recommend very carefully using a fine-tooth hacksaw to saw off as much as possible, then use files to file off the remainder.
You can use a sanding drum in the Dremel for the final stage, but you have to be very careful not to allow it to "run away" over areas you don't want scarred.

One trick is to use light sheet steel or brass shim stock to make a shield to protect the barrel.
Just cut a hole in the sheet that will be a close fit over the ramp, then wrap the sheet around the barrel and secure with heavy tape, leaving the ramp exposed and sticking up through the hole in the protective shield.
This will protect the barrel surrounding the ramp if/when you slip with a file.

Be careful not to cut into the barrel with the hacksaw, but get as much of the ramp as you can to reduce the amount of filing needed to get the rest off.

When you get close to the barrel, switch to a finer cut file and use that remove the last bit.

With the ramp off and the metal reasonably smooth, I'd recommend a coat of some type of gun coating to cover the bare metal and prevent rust.
Brownell's sell Alma-Hyde II which is a tough epoxy that requires no baking.

I doubt the front sight will need much of anything to make a more or less permanent installation, other than possibly some Loctite 242 (Blue) on the screws, or if you're sure you won't be removing it, Loctite Red, (Permanent).
These sights clamp on pretty tight.

For drilling and tapping, nothing beats a drill press.
Since the bottom of the 870 receiver provides a flat, level surface, you can put it on the drill press table and that will level the receiver.
There are any number of ways to clamp it in place.

Centering the holes is harder than it looks (Must be, a lot of "professional" gunsmiths can't seem to drill a centered, straight hole).

Locate the holes and center punch with a good center punch to locate and start the drill.

Use the best drills you can buy, and MAKE SURE to use a good drill lubricant like "Flute Juice" or any other machine shop drilling and tapping lube.

The drill press will keep the holes straight IF you've got a good setup.
One trick of the trade, is to cut off the shank of the drill so you have only a short section sticking out of the chuck.
This makes the drill less flexible and prone to "wonder".

After you drill ONE hole leave everything as is, UNPLUG the drill press, and unhook the drive belt. Remove the drill and insert the tap. Turn the chuck by hand to tap the hole. This will insure a straight properly tapped hole and will reduce the chances of a broken tap.
Again, use the best tap and lube with a tap lube.

After that hole is done, set the drill up for the next hole.

To keep a drill to a certain depth, either use the depth gage on the drill press, OR use some steel tubing or even a small steel block 5mm thick to make a stop that will fit over the drill. Simply fit the stop over the drill and adjust the drill in the chuck so that only 5mm can stick out before the chuck contacts it.
This will stop the drill after 5mm depth.

You can do much the same thing with a hand drill, but keeping the holes straight and square is nearly impossible, even for people pretty good with a hand drill.

If you don't have access to a drill press, I'd think real hard about taking the bare receiver and magazine tube to a machine shop and let them do it.

 

[Jenrick]

For the dremel inclinded among us (hey I'm one of them). Dremel actually makes a fairly decent drill press table, that you hook your dremel into. Works fairly well, and if you know what you're doing not to hard to modify to fit larger items.

-Jenrick

 

[Rocco Stag]

Many thanks for your insight!

Fellows,

I'm indebted to both of you (and especially to Dfariswheel) for the replies and valuable information shared. THANKS!

Regarding the drilling and tapping section of the installation, I had surmised it would be a real bear to accomplish and your commentary confirms it quite clearly. Right now I'm weighting in these issues BEFORE commencing.

After all, the piece is a 1968 vintage 870 Police and just a dandy to shoot as-is, not to mention quite accurate too!

Well, it's back to wearing the ol' thinking hat then. THANK you heartily, fellows!

Cheers,

Rocco

 

[target1911]

my suggestion is just go buy another 870 for the project. I wouldnt want to risk damage to an old gun like that. I just bought one in great shape at a pawn shop for $110.... and another for $150. I see them all the time in that price range. Good Luck

 

[Rocco Stag]

I wish!

As I live outside CONUS in a largely NPE (country-wide), that is a non-option. Unfortunately so, if I might add!...

Cheers,


Rocco