[XCR-Fin]

I have a Trijicon TA55 (5.5x55) on my 5.56 HK SL8-1. Sure it's overkill but I love it...super clear glass, great light, batteryless illumination... It's calibrated for 5.56 and I've fired it out to 500m using the numbered hash marks on the reticle. They're convenient as hell and spot on with a 69 grn Sierra Matchking I'm looking to buy a 6.8 and/or a 6.5 XCR but am worried I'll need two different ACOGS judging from this ballistic comparison (small PDF download) http://shootersforum.com/attachment.htm?s=be459b99ca9012f1e6bead511dccdce8&attachmentid=446&d=1076081272

Looks like the 6.8 mirrors the 5.56 close enough that I could live with it but the 6.5 is closer to the 7.62 up to 400m then its in its own class.

Anybody have any thoughts on this?.......other than sell my SL8 and get another ACOG. 6.8 + ACOG users out there?


UPDATE: SEE BELOW MESSAGE FROM TRIJICON

 

[XCR-Fin]

I asked Trijicon the question above. Here was their response:

Dear "XCR-Fin",

Thank you for your interest in Trijicon products. The company is investigating the possibility of a 6.8 calibrated ACOG that could be available "down the road." In the mean time, we can recommend one of our .223 calibrated 4x32 models zeroed approximately 1 inch high as a good compromise given the 6.8 SPC's effective range. Our .308 models are actually fairly close for the Grendel. Please contact us if you need further assistance.

Sincerely,

Customer Service
1-800-338-0563
www.trijicon.com

-----Original Message-----

Question/Comment:
I have a TA55 on my .223 and love it. I recently purchased a 6.8mm and a 6.5mm Grendel. Which scope calibration to you recommend I buy for those calibers given your scopes are calibrated for either .223 or .308.

Thank you,
"XCR-Fin"

 

[RedFalconBill]

A 7.62 ACOG can be used on a 6.5 Grendel.

Bill A. has shot his uppers extensively with ACOG's to confirm this.

Check up his site, 65Grendel.com, for more information. FWIW, I would use a TA11C and its 'Donut of Death".

As for the 6.8, I think that what Trijicon told you vis-a-vie the 5.56 ACOG's reticule is good information.

 

[XCR-Fin]

A 7.62 ACOG can be used on a 6.5 Grendel.

Bill A. has shot his uppers extensively with ACOG's to confirm this.

Check up his site, 65Grendel.com, for more information. FWIW, I would use a TA11C and its 'Donut of Death".

As for the 6.8, I think that what Trijicon told you vis-a-vie the 5.56 ACOG's reticule is good information.

Right now I'm leaning toward the TA31TRD. I like the precision of the illuminated cross hairs. The donut looks like a great reticle for quick target acquisition, but I'm strictly benching my 6.8 XCR. Any idea of the MOA size of the center of the donut? If I move to offhand I'll use the red dot on top.

I would have loved the TA31ECOS reticle (pictured below) due to the thin posts and open cross hairs at 7,8,9,10, (chances of shooting that far are slim for me but I like the idea) but I called and they said it's only offered in that scope which is Flat Dark Earth :'(. The lady at Trijicon said she gets lots of calls asking the same thing so "down the road" it's possible they'll offer it in black. In my experience however those roads are very long.

 

[RedFalconBill]

A 7.62 ACOG can be used on a 6.5 Grendel.

Bill A. has shot his uppers extensively with ACOG's to confirm this.

Check up his site, 65Grendel.com, for more information. FWIW, I would use a TA11C and its 'Donut of Death".

As for the 6.8, I think that what Trijicon told you vis-a-vie the 5.56 ACOG's reticule is good information.

Right now I'm leaning toward the TA31TRD. I like the precision of the illuminated cross hairs. The donut looks like a great reticle for quick target acquisition, but I'm strictly benching my 6.8 XCR. Any idea of the MOA size of the center of the donut? If I move to offhand I'll use the red dot on top.

I would have loved the TA31ECOS reticle (pictured below) due to the thin posts and open cross hairs at 7,8,9,10, (chances of shooting that far are slim for me but I like the idea) but I called and they said it's only offered in that scope which is Flat Dark Earth :'(. The lady at Trijicon said she gets lots of calls asking the same thing so "down the road" it's possible they'll offer it in black. In my experience however those roads are very long.

The inner ring diameter is 2 MOA, the outer ring diameter is 4 MOA.

You can do some mighty fine shooting with the donut. On a flattop AR, monolithic upper (a la XCR/MRP) I also like its extra eye relief, which give me a bit more lee way in mounting it.

If all you are doing to benching your XCR, just get the Burris FFII Tactical in Warne rings and save the extra cash for spare ammo/magazines/cleaning kit/spare parts.

FDE is the 'new' color of the Army. No more Black, Tan, or OD Green.

Not a big fan of having the RDS above the optic either. Just have it in a 45 degree mount in front of the ACOG. It IS an emergency sight, until you can get your scope off and flip up your BUIS.

 

[DSM]

I shot their TA01NSN (cal'd for 14.5" 5.56) on an 18" 6.8 AR and it actually worked great to 500yds. Once zeroed, the reticle matched the round very well with repsect to using a 12 o'clock hold to the target. No fuss and easy to get use to in practice.

 

[XCR-Fin]

Hello.

I am in a similar position.

Thinking of getting an ACOG.

What did people get and how did they work out ?

Got your PM too. I still haven't put any glass on my 6.8 (picked it up a month ago and funds are tight). I've shot my friend's Barrett REC7 (6.8mm) with the Trijicon TA31TRD several times. The first time I shot it I didn't care for the reticle. It was really bright and gave off the dreaded plume which blurred the 200 and 300m crosshairs. The second time I shot it we were under a covered shooting bench and it looked great. The red dot was really nice too.

I wish the illumination strip was adjustable like the collar on the TA648 models. I guess you could MacGyver something to deal with the really sunny days though. I'll keep you posted on what I end up with.

 

[XCR-Fin]

UPDATE:
I was recently at a hunting convention that Trijicon was attending. The rep there said they're releasing a 6.8mm calibrated scope in 2009 and showed me the brochure that listed the 4x32 TA31F as being calibrated in 6.8 with the chevron reticle. He had another sheet that said the horseshoe dot reticle may also be available in that model but it wasn't in the brochure.

I realize there isn't much difference in the 5.56 and 7.62 calibrated models until you get past 300 yds but as long as they're making one in 6.8 I think I'll wait to get it.