DA Grizzly customization - UPDATED - calling it done!

Well I believe I have it fixed :) The gun is going to TacOrd tomorrow (mail) for remchtoke install on the 12.5" barrel and cerakote of the gun and 2 barrels.

Here is the fix to my receiver "ledge". Someone asked earlier and YES - the top of a Grizzly receiver IS thicker at the heel than a real Remington. Not anymore (on mine). This is about an hour if filing, measuring, filing, measuring, and then a polish to 200 grit. Matches the Remington heel profile perfectly now. Yes, I know, I'm anal and it's only a cheap shotgun.

IMG_0375_zpsaqtvjwpf.jpg


Now for more fun and games. I got a new 28" express barrel from Dlask ($140). Well, it turns out the Grizzly barrel alignment stud on the front of the ejector assembly on a Grizzly is slightly higher on the receiver than on a Remington. This means remington barrels are about 4 degrees out of index. For a bead sight, not a big deal, but with a vent rib, it's really noticeable when sighting down the barrel. I want this gun to be dual-purpose: a 12.5" choked bbl for general use and a 28" VR as my backup/loaner waterfowl shotgun. (I normally shoot a Beretta Xtrema2).

Well you CAN fix an indexing issue if you really want to put the effort into it. First, you file the TOP of the locator slot on the barrel (opposite the extractor cut), until the barrel indexes. then you mount the barrel and use feeler gauges to see how much of a gap is BELOW the locator stud in the barrel slot. You get a piece of shim stock slightly thicker than that and using oxy-acetylene, you silver-solder the shim to the bottom of the slot and file to shape. You have to be quick wit the torch, you don't want the steel at the locking recess to change colour - that would be bad. The shim will make the slot too tight. Now you slowly file the shim down until the barrel locates on the stud smoothly.

Voila! this will all disappear once the cerakote is on it, but here you can see the shim (in the white):
IMG_0377_zpsb5q2bl8t.jpg


Finally, the Grizzly's ejection port is about 1.5mm TALLER than the remington port. This makes no functional difference, but Remington barrel extensions will stand proud of the ejection port. the fix is to file the curvature off the part of the remington barrel extension that would overhang into the ejection port like this:

IMG_0378_zps7qve5bsi.jpg


Now it fits OK. Sorry, I took the pic before I cleaned up the file marks.
 
Good work,sounds like your really making the gun yours.

It's a character flaw. I can never leave well enough alone. I always "improve" my stuff if something about it bothers me. Whether it's tuning lever guns, pump shotguns, building custom mausers, etc. I trained as a machinist and have a machine shop, a large selection of metalworking tools, and I'm mechanical engineer. So I guess it comes by me honestly. It helps that one of my good friends is a master gunsmith and we are always trading ideas - mostly he tells me about gunsmithing and I tell him about how to better use his machines.

I'm now thinking Magpul FDE metal with the black/charcoal Hogue furniture. It should be a nice contrast.
 
My Hogue stock I think fit well with my Grizzly.

It's possible some are machined closer to Remington profile than others. It yours fits well, consider yourself lucky :)

Realistically, we don't even know if CanAm gets all its 870 clones from the same factory consistently.
 
Well I think I'm calling it done. It's cycling well, looks awesome, and I like it :)

181fe232-bab5-4268-947a-42ac7787e659_zpsg94rcuex.jpg

IMG_0422_zpspjz88ngz.jpg

IMG_0424_zps46ubxvi0.jpg

IMG_0425_zpsfqfkwyrm.jpg

IMG_0426_zpsfmoewn5e.jpg


-Receiver re-contoured to fit standard remington stocks.
-S&J follower
-Remington Flexi-Tab elevator
-Williams large button lefty safety
-Threaded for Remchtoke (Improved Cylinder in it now)
-Remington tactical bead sight base and bead silver soldered on
-Hogue stock set
-FDE cerakote refinish.

Thanks to TacOrd for the tube threading, sight install and cerakote. They did a great job.
 
Last edited:
Don't get me wrong, the stock snugs in tight, it makes full contact all around, the issue is that there is a sharp ledge, about 1mm to 1.5mm high, around the top of the stock as shown in my fist photo.

The other issue is that the Remington barrels I installed to check fit were all indexed off about 4 degrees clockwise (viewed from the back like when holding the gun). I have a 28" express bbl I just fitted to the Grizzly so I can use the shotgun for waterfowl when not mounting the 12.5" tube. I had to file the indexing slot upward 25 thou and silver solder a 25 thou shim to the bottom of the indexing slot to get the vent rib to top dead centre.

It fits and looks great now.

The Remington barrel would have worked before, but the vent rib being out of index was really visually annoying. These are definitely not a 100% dimensionally accurate copy of a Remington. Should be fine once I get all the kinks out of it.

I've never seen one that didn't have the index issue, but I've only dealt with maybe 4 different receivers and 6 or so barrels, they seem consistently off despite what others report.

Nice work!
 
Last edited:
Was the flexi-tab an easy swap? Where did you get the flex tab carrier from?

I local gun shop has scrapped some 870's over the years for various reasons. I got 2 flexi-tab carriers (used) from them. You can get new ones from Brownells for around $20 US each. (the second one is going in a Wingmaster build)

To fit one, you either have to use a remington pin, or ream out the carrier's mounting holes by about 5 thou as the DA pin is 5 thou larger in diameter then a Remington pin. You can do this in 5 seconds with a cordless drill if you have the right size bit.

One of mine was a drop-in fit, the other carrier needed a couple file strokes on the hump that the bolt hits to drop the carrier back down when cycling the action. The hump was slightly too tall to fit into the recess in the bottom of the bolt, just enough to make shells hard to load into the mag. A couple file strokes later, and all was fine. Gun's been cycle tested and even the cheap winchester No.4 shells are cycling perfectly.

Realistically, I've had to fiddle around fitting new carriers to real Remingtons as well. They are a stamped metal part and sometimes are just a hair "off", needing very minor bending, tweaking or a few file strokes to work optimally.
 
Right, some are stamped DA Grizzly, some HP9, some PD12.

I could be wrong, but I think ALL the guns CanAm orders are marked as DA Grizzlies. Also, the are NOT marked "made in China". So clearly, CanAm is dealing directly with a factory or middle man in the PRC who is ensuring all the guns they order meet an agreed specification of some sort.

I will say, this particular gun was really well made. Like MUCH better than any other Chinese-made gun I've ever purchased. The fit and finish was top notch everywhere, the parkerizing (or matte blue?) finish was smooth, even, and with less machine marks under the finish than a real Express. If I did not know better, I would have guessed it was not Chinese made.

The honest "flaws" on the gun, as it came to me, included:

1) Real remington barrels were out 4 degrees on index in the DA receiver. The Grizzly barrel it came with indexed perfectly though.
2) The direct-mount bead sight was really too low, making the gun shoot high. I suspect this is a cost cutting choice CanAm made when spec'ing the gun.
3) The carrier/elevator was not a flexi-tab model like on a modern Remington.
4) The magazine follower was of poor quality, but then, they are also poor on a new Remington.
5) The ejection port is more "squarish" than on a Remington, which has very rounded ends. This is an aesthetic difference - no functional difference.
6) The stocks the gun came with fit the receiver perfectly, but remington and aftermarket stocks did not fit perfectly out of the box. The foreshock tube is larger diameter than on a remington and I had to scrape/sand the inner diameter of the hogue forestock a few thou so it would fit (tightly) on the tube. Also, the hogue buttstock left a "lip" (detailed above) at the back of the receiver. If you are refinishing the gun anyway, you can file down the contour, re-polish and refinish as I did. Now Remington stocks fit perfectly.
7) The OEM furniture is solid plastic. And it seems to be some sort of nasty recycled plastic that while functional, smelled awful like off gassing chemicals. This seems common on most asian guns these days. Good furniture is a must-do upgrade on these guns that will also reduce weight significantly.

Everything else about the gun was great. In many way better than an Express 870. The action was also MUCH smoother than an express action, right out of the box. The bolt and carrier plate (the part the bolt sits on) were better finished than an express out of the box and the extractor is NOT a MIM part. The receiver also has a serrated guide line along the top to assist in aiming, and it's drilled and tapped from the factory for either ghost ring sights or an optic base. The gun had sling QD studs pre-installed with cheap-looking swivels mounted in them. I removed the cheap swivels, but hey, they were included free, which is more than I can say for any express model.

Surprisingly the trigger plate assembly is REALLY well made. The trigger bow is a little larger than a real Remington's bow, with just enough room to comfortably use a gloved finger. There are no machining marks in the aluminum, which looks to be smooth powder coated (?) a matte black. It's actually a nicer trigger assembly than all but a Wingmaster part, in my opinion.

I would definitely do this project again. VERY happy with the results. More so than putting a choke-less 14" remington barrel on a cheap express receiver. I'm surprised more people have not jumped on these DA guns specifically to do upscale mods.
 
Last edited:
I have a Made in China stamped PD12 Grizzly from Canadammo that is identical to my DA stamped Grizzly from Canadammo. They've been selling them for a while now, so it's likely different incarnations have been had over time.
Largely, they can be inconsistent gun to gun from my experience and other accounts.
My DA Grizzly has a nicer matte gray/black finish, but has a rougher more gravely action compared to my PD12 Grizzly which has a cruder, darker black matte finish and very smooth and slick action.
 
Last edited:
Interesting. Well mine's from the current batch they are selling right now, no complaints with the product, I'm very happy with it. None of the changes I made were strictly "needed", but they have made it a much better overall gun in my view.
 
Back
Top Bottom