ISD AR Carbine 2-Piece Drop-In Rail
by esrice and lovemywoods
Photos by Jenn Rice of HisKids Photography
With so many different manufacturers, styles, and prices, the AR rail market is one of broad diversity. This is a good thing, as manufacturers compete for that space between your upper receiver and front sight base, bringing you many options for you to choose from.
Whether you need to mount a bipod, sling, vertical foregrip, or light/laser, a rail system gives you the diversity needed to put them exactly where you want them, thereby making you a more efficient shooter.
Now, I'll admit I'm typically the first person to turn up my nose at any rail priced under $150. The materials, machining, fit-and-finish, and overall look of these rails have traditionally been severely lacking. But, lovemywoods had a Spike's M4 in need of a rail system, and I had heard some "too-good-to-be-true" stories about an inexpensive rail Cwood was pushing, so I decided to put it to the test.
Enter the ISD AR carbine 2-piece drop-in rail, from Indiana Supply Depot. In the world of rail systems the ISD rail falls into the non-free-float, super-easy-to-install, sub-$100 category. Other contenders in this category are typically poor-quality rails from UTG, NCStar, and other Chinese manufacturers. I'm here to tell you why the ISD rail, made right here in Indiana, is head and shoulders above the competition.
First, some specs:
First impressions were positive. The rail comes in a simple box with installation instructions and 5 screws. Although mounting the rail only requires 4 screws, I appreciate the attention to detail in adding a spare (not shown).
The rail seems a bit heavier in the hand than others I've handled, but those others are also 3-4x the price. The machining and anodizing appears to be surprisingly good quality. The overall design is simple and straight forward, and appears to somewhat mimic the Knight's Armament RAS rail.
The upper rail is T-marked with subdued, non-filled numbers.
At the forward end of the rail, on each side, there is a QD sling swivel socket with rotation-limiting cuts-- something VERY rare on a sling this inexpensive. This feature is very nice when using a 2-point sling with QD swivels, as it keeps your sling from becoming tangled. Although I personally prefer the sockets on the opposite end, many prefer them exactly as they are.
The screws that lock the two pieces together are of good quality. They are small enough to not be noticed, but large enough, and long enough, to seat without stripping or cross-threading. The fact that lovemywoods and I actually installed and removed the rail twice easily speaks to the quality of the machining. (pic is underside of rail)
Now, what rail is complete without an assortment of AR goodies to hang off of it? lovemywoods and I mounted several different accoutrements, to ensure that the slots were in spec.
First, our blank canvas.
A Magpul RVG mounted up easily and solidly.
A TangoDown VFG went on in seconds, and locked up tight.
A Harris bipod in LaRue QD mount went on with no issues.
We tried two different lights and mounts - a Streamlight PolyTac in VTAC mount, and a Surefire G2LED in a Surefire mount. Both locked up just fine. Chris Costa would be proud!
We also tried 3 different rail covers by Magpul-- XT, XTm, and ladders.
Here we discovered a very cool feature. Because the QD socket takes up only two rail spaces, and because both the XT and XTm covers only use every-other slot to lock onto the rail, you can actually install the covers right over the QD socket, concealing it completely. Also, with the XTm covers, you can fit up to 4 pairs on an unused side, with them overhanging the front just slightly. (only half the XTm pieces are shown in the below pic, so you can see what they cover) Ladder rails, obviously, won't go over the QD socket, and must be cut to fit.
I said earlier that this rail fell into the "super-easy-to-install" category. But just how easy?
Here is what you'll need to install this rail:
Step 1: ENSURE YOUR WEAPON IS UNLOADED!
Step 2: Remove original handguards. If you have the tool, great. If not, just get a second set of hands to pull down on the delta ring while you pry out the top and bottom handguard.
Step 3: Reverse the last step, but this time use the new ISD rail pieces. Top section goes in first, with QD slot toward the muzzle, and T-marks on top.
Bottom section is then fit into the top section, and snapped into place. (the below picture is a bit deceiving, as the top portion of the bottom rail actually locks in first, and then the bottom portion)
Ensure that the rail pieces fit together, and that they are locked squarely into place by the delta ring. At this point you may notice some wiggling. Don't worry, as everything will lock down solidly when the screws are installed.
Step 4: From the underside, install and tighten the 4 supplied screws. Treating the threads with blue Loctite is always a good idea.
Viola!!
Now, there are a few things I don't personally like about this rail. First, I don't like that it contacts the barrel-- I prefer a free-floating rail. I also don't like the gap between the upper receiver and the top rail-- I prefer a "monolithic" look with a continuous upper rail. I found it comparatively heavy-- but certainly not prohibitively so. As mentioned above, I would also prefer for the QD slots to be on the opposite end.
So who would I recommend this rail to? I would recommend it to anyone looking for a solid way to mount accessories, who doesn't mind trading a little bit of weight for a drastic cut in price (compared to other rail systems). If your needs don't require free-floating capability, and you run a 2-point sling, this rail is for you. If you like the added benefit of supporting a local manufacturer, then I think you'll be very happy with what Indiana has produced in the ISD 2-piece drop-in carbine rail.
AFAIK, this rail is sold exclusively through Indiana Supply Depot. You can visit their website at Indiana Supply Depot to purchase, or you can PM Cwood here on INGO directly. According to their website and INGO Advertiser Forum, they are running this rail on special for the month of January, at a price of just $69.99. You can also pick one up at this price at next weekend's Indy1500 by stopping by the ISD booth, located next to Raven Concealment and Tactical Shotgunner.
I'd be happy to answer any questions I can about my experience. I'm sure Cwood will be along soon enough and he can answer any other questions.
*************************
Original thread here: https://www.indianagunowners.com/fo...2-piece_drop-in_carbine_rail_for_ar-15_a.html
Whether you need to mount a bipod, sling, vertical foregrip, or light/laser, a rail system gives you the diversity needed to put them exactly where you want them, thereby making you a more efficient shooter.
Now, I'll admit I'm typically the first person to turn up my nose at any rail priced under $150. The materials, machining, fit-and-finish, and overall look of these rails have traditionally been severely lacking. But, lovemywoods had a Spike's M4 in need of a rail system, and I had heard some "too-good-to-be-true" stories about an inexpensive rail Cwood was pushing, so I decided to put it to the test.
Enter the ISD AR carbine 2-piece drop-in rail, from Indiana Supply Depot. In the world of rail systems the ISD rail falls into the non-free-float, super-easy-to-install, sub-$100 category. Other contenders in this category are typically poor-quality rails from UTG, NCStar, and other Chinese manufacturers. I'm here to tell you why the ISD rail, made right here in Indiana, is head and shoulders above the competition.
First, some specs:
IndianaSupplyDepot.com said:
First impressions were positive. The rail comes in a simple box with installation instructions and 5 screws. Although mounting the rail only requires 4 screws, I appreciate the attention to detail in adding a spare (not shown).
The rail seems a bit heavier in the hand than others I've handled, but those others are also 3-4x the price. The machining and anodizing appears to be surprisingly good quality. The overall design is simple and straight forward, and appears to somewhat mimic the Knight's Armament RAS rail.
The upper rail is T-marked with subdued, non-filled numbers.
At the forward end of the rail, on each side, there is a QD sling swivel socket with rotation-limiting cuts-- something VERY rare on a sling this inexpensive. This feature is very nice when using a 2-point sling with QD swivels, as it keeps your sling from becoming tangled. Although I personally prefer the sockets on the opposite end, many prefer them exactly as they are.
The screws that lock the two pieces together are of good quality. They are small enough to not be noticed, but large enough, and long enough, to seat without stripping or cross-threading. The fact that lovemywoods and I actually installed and removed the rail twice easily speaks to the quality of the machining. (pic is underside of rail)
Now, what rail is complete without an assortment of AR goodies to hang off of it? lovemywoods and I mounted several different accoutrements, to ensure that the slots were in spec.
First, our blank canvas.
A Magpul RVG mounted up easily and solidly.
A TangoDown VFG went on in seconds, and locked up tight.
A Harris bipod in LaRue QD mount went on with no issues.
We tried two different lights and mounts - a Streamlight PolyTac in VTAC mount, and a Surefire G2LED in a Surefire mount. Both locked up just fine. Chris Costa would be proud!
We also tried 3 different rail covers by Magpul-- XT, XTm, and ladders.
Here we discovered a very cool feature. Because the QD socket takes up only two rail spaces, and because both the XT and XTm covers only use every-other slot to lock onto the rail, you can actually install the covers right over the QD socket, concealing it completely. Also, with the XTm covers, you can fit up to 4 pairs on an unused side, with them overhanging the front just slightly. (only half the XTm pieces are shown in the below pic, so you can see what they cover) Ladder rails, obviously, won't go over the QD socket, and must be cut to fit.
I said earlier that this rail fell into the "super-easy-to-install" category. But just how easy?
Here is what you'll need to install this rail:
- Flat-head screwdriver
- Handguard removal tool (or a second set of hands)
- 5 minutes time (total)
- Blue Loctite (optional, but recommended)
Step 1: ENSURE YOUR WEAPON IS UNLOADED!
Step 2: Remove original handguards. If you have the tool, great. If not, just get a second set of hands to pull down on the delta ring while you pry out the top and bottom handguard.
Step 3: Reverse the last step, but this time use the new ISD rail pieces. Top section goes in first, with QD slot toward the muzzle, and T-marks on top.
Bottom section is then fit into the top section, and snapped into place. (the below picture is a bit deceiving, as the top portion of the bottom rail actually locks in first, and then the bottom portion)
Ensure that the rail pieces fit together, and that they are locked squarely into place by the delta ring. At this point you may notice some wiggling. Don't worry, as everything will lock down solidly when the screws are installed.
Step 4: From the underside, install and tighten the 4 supplied screws. Treating the threads with blue Loctite is always a good idea.
Viola!!
Now, there are a few things I don't personally like about this rail. First, I don't like that it contacts the barrel-- I prefer a free-floating rail. I also don't like the gap between the upper receiver and the top rail-- I prefer a "monolithic" look with a continuous upper rail. I found it comparatively heavy-- but certainly not prohibitively so. As mentioned above, I would also prefer for the QD slots to be on the opposite end.
So who would I recommend this rail to? I would recommend it to anyone looking for a solid way to mount accessories, who doesn't mind trading a little bit of weight for a drastic cut in price (compared to other rail systems). If your needs don't require free-floating capability, and you run a 2-point sling, this rail is for you. If you like the added benefit of supporting a local manufacturer, then I think you'll be very happy with what Indiana has produced in the ISD 2-piece drop-in carbine rail.
AFAIK, this rail is sold exclusively through Indiana Supply Depot. You can visit their website at Indiana Supply Depot to purchase, or you can PM Cwood here on INGO directly. According to their website and INGO Advertiser Forum, they are running this rail on special for the month of January, at a price of just $69.99. You can also pick one up at this price at next weekend's Indy1500 by stopping by the ISD booth, located next to Raven Concealment and Tactical Shotgunner.
I'd be happy to answer any questions I can about my experience. I'm sure Cwood will be along soon enough and he can answer any other questions.
*************************
Original thread here: https://www.indianagunowners.com/fo...2-piece_drop-in_carbine_rail_for_ar-15_a.html
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