11 replies to this topic

[promod1385]

I have sold of my Optics 3G rifle and plan on shooting the next couple seasons with an Irons gun I recently put together. Its a 16" DPMS Dissipator barrel that I have a carry handle set up for and a national match front sight post.

I currently have the rifle zero'ed at 100yds. Been reading online about RIBZ, IBZ, and various other sight in methods. What does everyone recommend for a 3gun zero? Most of our local shoots are a max of 250 yards. I am heading to the range today plan on re-zeroing at 200 and seeing where that puts my hits at 25-50yds.

[Ten-X]

I have a 200 yard zero. It shoots within 1.5" from 50 to 200 which is well within whatever we shoot so I just hold center for nearly everything. I can hold over at 300 and have click settings setup for anything longer. I just shot at 375 and since the shot was in the middle of other closer targets I didn't take the time to click, just held over and shot.

I tried a 300 yard zero too but I didn't like holding under for the 100-200 shots. I guess I would maybe consider a different zero for different matches but all the matches I've shot are 95% 200 and in.

Edited by Ten-X, 24 June 2012 - 01:35 PM.

[Ten-X]

Double post.

Edited by Ten-X, 24 June 2012 - 01:34 PM.

[P.E. Kelley]

Iron Sights and the 3 gunner

This may help you to improve your game.

It worked for me.

[Dan Sierpina]

I currently have the rifle zero'ed at 100yds. Been reading online about RIBZ, IBZ, and various other sight in methods.

I'm sorry, I am old, feeble, and not up on the "tactical" speak. What the heck is RIBZ and IBZ?

[Vespid_Wasp]

I currently have the rifle zero'ed at 100yds. Been reading online about RIBZ, IBZ, and various other sight in methods.

I'm sorry, I am old, feeble, and not up on the "tactical" speak. What the heck is RIBZ and IBZ?

If I recall correctly:

Revised Improved Battlesight Zero
and Improved Battlesight Zero

[promod1385]

I zeroed the Dissipator at 200meters this weekend. I am really enjoying shooting this gun! The recoil impulse seems much shorter than my 20" gun.


I wont have a chance to work on any longer range stuff until I visit my buddy in SD next month.

Good read Mr Kelley! I will try and get dialed in at 400yds on my next trip to SD. Of my 3 local 3gun shoots only one has access to a 300yd range and the other two are 200 and 100yd max.

The Dissipator seems like an advantage on the shorter/pistol bay type courses of fire we encounter here in the midwest.

[Ten-X]

Is it a real dissy with a rifle length gas system. I have not seen one of those. The rumor is that they are sensitive and tough to tune, having to mess with ports and carriers and buffers. The only dissy I have seen are the mid length gas systems under the handguard. Great choice btw. Love dissy's.

[promod1385]

Is it a real dissy with a rifle length gas system. I have not seen one of those. The rumor is that they are sensitive and tough to tune, having to mess with ports and carriers and buffers. The only dissy I have seen are the mid length gas systems under the handguard. Great choice btw. Love dissy's.

Yep its a "real" one. I was concerned about buffers and had a n H, H3 and rifle buffer on hand when I put the rifle together. They all ran and I liked the feel of the rifle buffer the most so that's what I am running.

Its got a Bravo Company BCG (I am a big BCM fan boy, I cant say enough good things about there bolts).

[nick romero]

Great information in this post, the article on 3 gunners helped me,im planning on shooting irons at a local 3 gun match in august. im going to be using the diamondhead sights

[Nuke8401]

Since long-distance targets present a small aiming area, a 6-o’clock hold is generally preferred. This allows the shooter to have a good visual hold point without having to look at the target to maintain the hold.

I shot irons for one season and some of the issues I struggled with were:

- In bright sunlight on the front sight, glare can be an issue. I guess there are several ways to combat this, old timers use a "smoker" to make the front sight a flat black, Birchwood Casey has sight black in a spay can that does pretty good job. You can spray it on for one stage and wipe it off for the next. Another way is with a hooded front sight.

- Low contrast/dark target. At the AR 15 pro/am there was a MGM flasher (10" steel) in the shade at maybe 200 yds, bright morning sunlight on the shooter, morning haze close to the ground. I found my front sight disappeared in the dark background and I could not see my front sight. I later read where Bruce Piatt started out shooting irons in three gun and used a small FO front sight and a 6 hold and I started using that same set-up My link .050 width, and it worked well for me after I dulled the FO rod a little with a sharpie (the exposed length, not the tip you see when aiming). Otherwise in full sunlight the FO rod was blazing and made seeing distant targets a challenge even with a 6 hold. With it dulled I could still see it against a dark background/target and see a crisp outline of the front sight post in bright light.

- Going from close (5yds) to far (400yds) can be done several ways, going from larger to small peep is a little painful on the clock. I found if I had a short course say out to 100 yards I could just use the large peep and make good hits. If the COF was 0-300 I would just use the small peep and front and rear ears for close targets. Using the small peep with both eyes open and a good cheek weld is still pretty fast up close. If I were to do this again, and I might, I would work on using the large peep from 0-200 as I think accuracy would be sufficient once you got a handle on the change in elevation, I think there are some “same plane” rear apertures out there that would make this easier.

Good luck!

[Acespeedy]

I'm running a DPMS 3G with a PRI barrel mount front sight/gas block with a KNS precision .52 ball post front sight post and a Daniel Defense fixed rear with the CSAT rear aperature. So far the sight combo is running great. The small ball post sight helps shooting on the move and the CSAT rear sight helps if I have a few close range targets mixed in with some far steel. I typically get a "soft" zero at fifty yds POA/POI then I'll back off to 200 yds and get a hard POA/POI zero on paper at 200. With this sight combo it puts me 1.1 inches high at fifty/2.1 inches low at 25yds and dead on at 200 shooting 64gr Gold Dots. I also use the sight black from Birchwood Casey because it's easier to keep around compared to a carbide lamp, eventhough the lamp produces a "darker black."