Shot Some Long Range Yesterday at Mayberry

[Kevp]

I took my GAP Crusader out to Mayberry yesterday to verify some dope. I was shooting American Ballistics M118LR and FGMM. Both loads were 175gr. 3rd Rcn had told me that the American Ballistics 175s were not SMKs and you can see the difference. I was dialing +3.5 mils for the AB at 500yds and was getting pretty decent accuracy out of it. When shooting FGMM I had to dial down 3/10 of a mil. I believe both rounds are supposed to be at 2600 fps at the muzzle. That means either the AB is not that warm or the ballistic coefficient of that AB projo is not as good as a SMK. Ed Shell probably knows the answer to this already. I am but a babe in precision game. I have noticed consistency issues when shooting the AB at 100yds. I had one box (4 x 5 shot groups) where my groups really opened up. I followed that up with some FGMM and they went back to what I normally shoot so I know it was the ammo. I just thought some might find that useful.

The pictures are of a 5 shot group on a 10'x10" steel plate at 500yds. Granted steel is not a preferred method of shooting groups, but it sure is more fun. Anyway, when I got around to shooting groups, all the steel had been shot and we didn't have any paint. I shot this group on the least shot up plate. The first plate pic is unedited and the second pic I blurred out the area that had been previously shot. I don't think that is too bad for 500yds. Comments from the precision crowd?

 

[05dodgedaytona]

Nice.

 

[Tconfo]

That rifle is a beauty. Nice shooting by the way.

 

[Russ D]

Nice rifle , but I cannot tell from that steel where you are hitting.

 

[Kevp]

Nice rifle , but I cannot tell from that steel where you are hitting.

Russ,

It was all painted white except for that blurred spot. Five rounds went into that blackened area in the center.

 

[Russ D]

In that case I'd say that's pretty damn good.

 

[E.Shell]

....I was shooting American Ballistics M118LR and FGMM. Both loads were 175gr. 3rd Rcn had told me that the American Ballistics 175s were not SMKs and you can see the difference. I was dialing +3.5 mils for the AB at 500yds and was getting pretty decent accuracy out of it. When shooting FGMM I had to dial down 3/10 of a mil. I believe both rounds are supposed to be at 2600 fps at the muzzle. That means either the AB is not that warm or the ballistic coefficient of that AB projo is not as good as a SMK....

The 3/10ths down is just how Terry's gun happens to handle the point of impact difference at your zero range, and may not be the correct correction for your rifle.

While some rifles put slightly different ammo into the same group at the zero range, it is common to see some divergence here. My 24" .308 requires I dial 1-1/2 MOA down and 1/2 MOA over from my FGMM 175s to get on with the American Ballistics M118LR.

This does not indicate the M118LR is any faster in my gun, only that the zero must be adjusted when switching ammo.

Unless you verify zero at your zero range for both loads, differences in dialed data at longer distances has limited meaning. IOW, the 3/10ths Terry has to dial up to get the M118LR to zero is likely unique to his rifle and may or may not be right for yours, and skews any results you see at longer distances.

Two carefully executed three shot groups at your (100 yard) zero distance, one with each load, will tell the story pretty clearly and likely equalize everything else downrange, since it's been my experience that the FGMM 175s and AB M118LR track pretty closely beyond 1k.

 

[Lou45]

So that was you making all that noise while I was installing a new target frame on the adjoining pistol range. My helper took shrapnal in the belly at that time and thought he deserved the purple heart; what a wuss.

By the way, not bad at all for 500 yard shooting.

 

[Kevp]

The 3/10ths down is just how Terry's gun happens to handle the point of impact difference at your zero range, and may not be the correct correction for your rifle.

While some rifles put slightly different ammo into the same group at the zero range, it is common to see some divergence here. My 24" .308 requires I dial 1-1/2 MOA down and 1/2 MOA over from my FGMM 175s to get on with the American Ballistics M118LR.

This does not indicate the M118LR is any faster in my gun, only that the zero must be adjusted when switching ammo.

Unless you verify zero at your zero range for both loads, differences in dialed data at longer distances has limited meaning. IOW, the 3/10ths Terry has to dial up to get the M118LR to zero is likely unique to his rifle and may or may not be right for yours, and skews any results you see at longer distances.

Two carefully executed three shot groups at your (100 yard) zero distance, one with each load, will tell the story pretty clearly and likely equalize everything else downrange, since it's been my experience that the FGMM 175s and AB M118LR track pretty closely beyond 1k.

I think you misunderstood me Ed. This is all my gun and my corrections. Terry only mentioned to me that the AB projos weren't SMKs. I zeroed my gun at 100yds with FGMM. When I shoot the AB at 100yds, they are very close to my FGMM zero. At 500yds, I had to dial down 3/10 mil (+3.2 mils) to get the FGGM on target after shooting the AB (+3.5 mils).

 

[JamesBailey]

We had the AB and the FGMM on a chrono and the AB was running ~50fps faster, so I'm not sure if you are right that the AB's colder than FGMM. Also, I'm not sure that the AB are not SMKs - it is my understanding that they are. If they aren't, what bullet are they?

In terms of AB accuracy, I was having no problem with the round at 700, 900 and 1200 yds. It was tracking very nicely to my dope (I can send that to you if you wish).

That is a beautiful rifle - very nice setup. Congrats on that setup. No surprise that it shots that well!

 

[E.Shell]

I think you misunderstood me Ed. This is all my gun and my corrections. Terry only mentioned to me that the AB projos weren't SMKs. I zeroed my gun at 100yds with FGMM. When I shoot the AB at 100yds, they are very close to my FGMM zero. At 500yds, I had to dial down 3/10 mil (+3.2 mils) to get the FGGM on target after shooting the AB (+3.5 mils).

You're right, I did misunderstand.

I would maintain that if your rifle shoots them to a substantially different trajectory, especially one with more drop, it would be the exception to the norm.

 

[Kevp]

Ed,

What was interesting is that the AB tracked exactly to my Shooter ballistic program on my Droid. That was using my barrel length, twist, and the 175SMK out of the program's library which has correct ballistic coefficient. It told me to dial +3.5 mils which put me right on with the AB. It really surprised me when the FGMM shot high.