The Leupold FX-II Ultralight 2.5x20mm and the Defensive Carbine

[NH Shooter]

The best part of this discussion is it has us all thinking outside of the normally accepted optics. There really are some great choices beyond the typical LPVO or RDS that seem to have become entrenched as the standard look-no-further optic recommendations for the AR.

In any discussion about AR weight, there is a list of items that one needs to keep an eye on if they want to keep their rifle from becoming ridiculously heavy. IMO, each of the following should be carefully selected where ounces can add up to pounds on a finished rifle;

• Optics
• Optic mount
• BUIS
• Barrel
• Muzzle device
• Handguard
• WML
• Stock
• Buffer weight

If you start looking at the weights of any of these, you'll discover they vary dramatically. For example an A2 birdcage weighs under two ounces, a SF Warcomp 3.8 ounces. An Aero scope mount weighs 3.4 ounces, a Spuhr 9.4 ounces. The Magpul PRS stock weighs 28 ounces, the MOE Carbine Stock 8 ounces. You can chose an optic that weighs 6.5 ounces, or one that weighs north of 1.5 pounds. Accessories such as a WML will typically add 5 to 8 ounces (which is why mine is set up in a QD mount). It all adds up mighty quickly so chose wisely.

What I'm discovering in my current exercise is that to gain the desired longer range precision is going to cost 22 ounces/1.375 pounds between the barrel and optic. The rifle will end up weighing 8.5 pounds, which isn't terrible but certainly can be felt compared to its former 7.2 pounds. But I believe that the added (and carefully considered) weight gain will be worth it in terms of the improved precision capability and range-time fun factor.

Finally, a photo of a former configuration before I had learned all of this the hard way. It would peg a 10-pound capacity scale with me still holding some of its weight (probably weighed around 12 pounds) and had less precision capability (same barrel but 1 - 4 optic vs. 3 - 9) than my current 8.5 pound rifle;




If you don't want to end up with a boat anchor like the one above, watch those ounces!

[Borderland]

Earlier in this thread I said I was going with a RDS on my carbine. I went to the range on Friday and tried my new Vortex Venom on my Ruger Mini again. I had previously tried an old Venom and it worked OK on a cloudy day. It was sunny on Friday and it sucked at 100 and 200 yds. I guess my eyes aren't as good as I thought they were. When I got home I put the 1-4x VX-2 back on. You just can't replace good glass.

Now I have a Venom that's going to set in a box because I have nothing to put it on.

[NH Shooter]

The Trijicon 3-9 Cedo showed up today and I mounted it (leveled the reticle to a plumb line). Initial impressions are very positive.

My main concern and the first thing I compared is the performance of the new scope set on 3x to the 2.5x20mm Leupold. I was concerned I would be giving up "usability" compared to the Leupold. I am almost embarrassed to state that there is no comparison:

• The Trijicon on 3x is brighter (expected with the 40mm objective) and shockingly sharper with greater resolution and contrast
• Set to 3x, the eye box is at least as forgiving as the 2.5x20mm (but becomes more constrained at higher magnifications)
• While the 2.5x20mm always has a bit of shadow at the edges even with perfect alignment, the Trijicon is sharply defined
• The reticle is finer (especially the inner sections), which is preferable for the precision work but the outer posts still draw the eye into the center
• The reticle illumination IMO is excellent, though those who want "daylight bright" at high noon on snow-covered ground will probably be disappointed
• It's a lot bigger and heavier

I will be sighting-in the scope this weekend and evaluating it at the 9x setting. I will start a new thread dedicated to this scope so not to derail this one. And photos, of course.

[littlejerry]

The Trijicon 3-9 Cedo showed up today and I mounted it (leveled the reticle to a plumb line). Initial impressions are very positive.

My main concern and the first thing I compared is the performance of the new scope set on 3x to the 2.5x20mm Leupold. I was concerned I would be giving up "usability" compared to the Leupold. I am almost embarrassed to state that there is no comparison:

• The Trijicon on 3x is brighter (expected with the 40mm objective) and shockingly sharper with greater resolution and contrast
• Set to 3x, the eye box is at least as forgiving as the 2.5x20mm (but becomes more constrained at higher magnifications)
• While the 2.5x20mm always has a bit of shadow at the edges even with perfect alignment, the Trijicon is sharply defined
• The reticle is finer (especially the inner sections), which is preferable for the precision work but the outer posts still draw the eye into the center
• The reticle illumination IMO is excellent, though those who want "daylight bright" at high noon on snow-covered ground will probably be disappointed
• It's a lot bigger and heavier

I will be sighting-in the scope this weekend and evaluating it at the 9x setting. I will start a new thread dedicated to this scope so not to derail this one. And photos, of course.

Glad to hear. Looking forward to it.

I'm happy with my NXS currently but may pick up a Credo 3-9 for a 16" grendel.

[OlongJohnson]

If you don't want to end up with a boat anchor like the one above, watch those ounces!

The first one I built, the flat top came out to 5 lb., 10 oz. I had been reading about weights and that was supposed to be incredibly light, based on what I was seeing. All I did was pick a lightweight barrel profile (16 in.), the OG BCM KMR, and a CTR stock. Not even any special effort toward lightness. I still think it's a nice rifle, though I've built others with somewhat heavier parts. Still in the safe as the lightweight option.

[stomridertx]

This is your fault OP. I didn't realize how much I missed magnification. It's a decent chunk of weight gain, but the rifle was built with a lot of light weight components so it's not bad. I'm going to swap out the BUIS with a lower profile option which will take off a couple of ounces.

[NH Shooter]

I use a QD mount for the WML so all that weight doesn't have to permanently reside on the rifle. It goes into the safe with the WML mounted but if I don't need it (like during range sessions), it comes off.

[GyroF-16]

I use a QD mount for the WML so all that weight doesn't have to permanently reside on the rifle. It goes into the safe with the WML mounted but if I don't need it (like during range sessions), it comes off.

What kind of QD mount?

My Olight Odin came with one, but I’ve not seen others. I really like the idea.

[NH Shooter]

I use this Vltor mount which attaches to a short section of rail and will hold any light with a 1-inch body (I have plenty of those);

[SecondsCount]

......
If you don't want to end up with a boat anchor like the one above, watch those ounces!

If I had to sling the gun and carry it all day, every day, then I might be concerned about ounces. I like magnification as well as comfort when I am shooting. You can ditch the bipod and use a bag as a rest but the rest of that setup looks pretty similar to what I run, and I don't find it to be all that heavy.