870 monte carlo stock lift vs standard?

[rodregier]

Can I get a description of the amount of comb "lift" created by the Remington 870 monte carlo synthetic stock (#19487) compared to the corresponding standard synthetic stock (#18614)?

http://www.remington.com/products/accessories/gun-parts/synthetic-stocks/model-870-synthetic-stock-and-fore-ends.aspx

I've been examining point of aim/point of impact with the standard synthetic stock for my usage. It looks like I need a much taller comb height for my setup which includes a 4mm green Uni-dot P110 on a vent rib. I use the big Uni-dot to help with my vision cross-dominance issues as an alternative to re-learning how to shoot long guns left handed. (n.b. I'm not interested in making the effort needed to re-learn how to shoot long guns well left-handed.)

http://www.uni-dot.com/home/p100-DN-4mm.php

Using a Beartooth Comb Raising Kit leads me to believe I could use around 0.7 inches of comb lift.

http://www.beartooth-products.com/shop/vmchk/comb-raising-kits.html

With my stature of 6'2" @200+ lbs I suspect I would need more comb height even if I was using the original bead.

http://www.thehighroad.org/showthread.php?t=165162

 

[rodregier]

The product copy on Brownells claims the Speedfeed 870 Monte Carlo version raises the comb height by approx 0.750 (19mm). They are silent on the details specs of the Remington version (as is everyone else). Apparently Remington assumes the rest of the world doesn't need details specs on their accessories. {sigh}.

http://www.brownells.com/.aspx/pid=12712/Product/MONTE-CARLO-SYNTHETIC-SHOTGUN-STOCK

 

[Dave McCracken]

You may need more,Rod. I suggest cardboard, masking tape and a patterning board and an hour's time. Once you're established what you need, measure it and find or make a stock to fit you.

 

[rodregier]

Am I correct in assuming that what I want is a point of impact centered just above the front dot? The usage is informal skeet and perhaps bird hunting later.

No permanent patterning board available to me :-( I deployed a temporary patterning setup w/giant paper to confirm similar impact point for shot and slugs. I'm using slugs on paper as a way to iterate/calibrate POA/POI. (similar recoil to the shot load I use). It's not a perfect method compared to the patterning board, but it will get me into the ballpark much easier than the alternatives available to me.

I purchased a 12ga laser boresighter "shell", handy to try indoors dry fire to get the stock setup close. It works quite well, verified POA/POI result with two other shotguns that are *already* properly sighted in with slugs.

I'm using a Beartooth Comb raising kit that has dense foam spacers 1/2/4/8 thickness increments and a neoprene sleeve to figure out how much lift I need on the stock. Mix and match to get any necessary thickness.

I'm thinking that I can acquire and switch to the Rem Monte Carlo stock offering which will get me *much* closer to the correct lift, and then I can use less extreme spacing methods to add the smaller amount of additional I might need. If the Monte Carlo gives say .750" of lift, my experiments suggest that will get me close enough to the correct POA/POI that I won't need any additional spacing.

I'm using this 12ga boresighter, works just fine:

Yukon Advanced Optics
Sightmark Laser Bore Sight
12 Gauge Shotgun

http://www.bhphotovideo.com/c/search?atclk=Category_Binoculars+%26+Scopes&Ntt=12+gauge&ci=978&N=4294249681&cm_sp=Filters-_-Category-_-Binoculars_Scopes

Uses 3xLR44/357 silver oxide button batteries, 1 hr runtime. on/off by unscrew/tighten base cap. Red laser.

I know this isn't the "traditional" way of during such things, but it look very promising.

 

[Dave McCracken]

Traditional, Schmaditional. If it works.....

One note, rarely do slugs and shot loads share an impact point. My HD 870 has a divergence at 40 yards of about 7" or so. Do double check.

Otherwise, kudos. More folks should take the time to do something like this and get things right.

I like the 2 and 3mm F/O beads better than the big ones, but if it works for you...

 

[rodregier]

After due consideration, I have ordered a Rem factory synthetic Monte Carlo stock for the 870. I'll report on the extra "lift" detail when I receive my order. Fortunately I was able to find a Canadian online retailer who carries it (Wholesale Sports), which lets me avoid
the whole ITAR "export from US to Canada" issue with a US retailer. For some strange reason Brownells omits selling that variant as made by Remington, but sells the other Remington-manufactured variant, including the ShurShot™ variant for the 870. Curious.

http://ca.wholesalesports.com/storefront/firearms-accessories/stocks/model-870-synthetic-stock-fore-end-12-gauge/prod101175.html

http://www.pmddtc.state.gov/regulations_laws/itar_official.html

http://www.pmddtc.state.gov/regulations_laws/documents/official_itar/ITAR_Part_123.pdf

Assuming that the underside of both stocks are setup with the same drop, I'll pick a datum point that is the same on both and measure the two heights at that location.

The top location where my cheekbone is positioned over the Monte Carlo stock - extended to the bottom on both would seem to be the appropriate location to make the comparative measurement...

Opinions on the measurement setup solicited.

 

[rodregier]

Difference is at least 0.7" at the highest point in the Monte Carlo hump. The hump is sloped so the actual difference will depend on where your cheek bone indexes against the butt stock. The Monte Carlo stock comes with sling swivel at the rear directly below the highest point in the hump. I can't measure the height at that exact point because of the interference, so I measured just in front of the sling swivel.

With the sights I'm using, the amount of lift seems just about perfect.

Now I have fewer excuses for missing

I may yet look at adjusting the cast-off of the stock with some shims, but I doubt I will have to make a pronounced adjustment in that axis.