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Part of the bullet info gathering threads. Please just post the facts or your experience with the bullets. How they performed on game, the accuracy of the bullet and loading data that produced good accuracy. If you don't have any experience please let those that do provide the info for others to learn from.
 

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So far, my experience is limited to factory Full Boar 100 GMX ammo.

I have used them on hogs shot on both the ground and from the helo. There seemed to be no distinguishable difference between the 85 TSX and 100 GMX performance, when I shot pigs from the helo. If I hit them anywhere fore of the diaphragm, they were down with only one shot, and about 75% of those were DRT. Of all the hogs we have shot on the ground so far (about 10) there have been complete pass throughs, and 7 of those were DRT, neck or shoulder.

Accuracy is about 1 MOA from my 12.5" SBR's. Velocity of the factory round is a bit slow, so I am ready to load some bullets to see if I can hit 2600 from a 16" barrel.

Here is a still photo of a hog doing a somersault after being hit with the 100 GMX, from about 250 feet.




If You click on the link below, you will see the first pig, the biggest, DRT from the first GMX. The second pig I'm shooting at out of the camera's view, then the third I get with the second shot. The very last pig is the one that somersaults. I hit him with my second shot just at the base of the neck, and it was lights out!



VIDEO link: ------> [video]http://vid153.photobucket.com/albums/s233/dkred5854/killshot2.mp4[/video]


 

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Haven't shot any critters yet, but the full boar ammo is crazy accurate in my 18" stainless barrel. It shoots like sh!t in my 14.7", though. That one likes the 110TSX fortunately. I'll be using the GMX on deer this fall.
 

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Anyone have any load data?
From 6.8 SPC II - 18” ARP 1:11 barrel

100gr Hornady GMX [BC 0.310] – 2.295” COAL
2685 fps (28.5gr AA2200) used in testing below (resized Hornady, CCI 450)
2750 fps (29.5gr AA2200) near max for SPC II (new SSA brass, CCI 450)

I had some very good groups with 1200R but I found this powder so sensitive to temperature changes and erratic above 90F I don't recommend using it in the 6.8
 

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Finally got to shoot the factory GMX's today. 100 yards in an ARP barrel, 3/4". I also shot some factory sst's and they shot hole for hole with the GMX's



Sent from my iPhone using Tapatalk
 

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From 6.8 SPC II - 18” ARP 1:11 barrel

100gr Hornady GMX [BC 0.310] – 2.295” COAL
2685 fps (28.5gr AA2200) used in testing below (resized Hornady, CCI 450)
2750 fps (29.5gr AA2200) near max for SPC II (new SSA brass, CCI 450)

I had some very good groups with 1200R but I found this powder so sensitive to temperature changes and erratic above 90F I don't recommend using it in the 6.8
Xman, How erratic were the loads with 1200R? Can you give more detail?

I've loaded my GMX's with A2200 at 2.295 as you suggested above but I cannot do better than a 2 MOA Group. LWRC 16" Razorback is what I'm shooting. I decided to try the 1200-R but in reviewing your post I saw your comment. Now I'm really frustrated and don't know where to go from now. Hornady recommends 1200-R and Viht N-130 What else would you suggest? I hunt in Texas so temperature is an issue.
 

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RW, I feel lucky to have seen your post. Feel free to IM at any time. Here is a link to the work I did with 100 AB and 100 GMX (only had a few).

http://68forums.com/forums/showthre...Magazine-COALs&p=609107&viewfull=1#post609107

I only carried the 100 AB forward as a hunting load. I tracked its average mv over a year of range sessions and experienced over 200 fps variation. Above 90F, I also would have a single round drop 300 fps below the average for that particular range session. This happened during 4 different range sessions. The variation was so much I started testing with another chrony in line with mine and pursued temperature sensitivity testing. I found my chrony was spot on and 1200R to be the most temperature sensitive powder I've used. I've have since stop using it even though it was the most accurate powder I used in the 6.8 (during a single range session).

Did you use a chrony on you loads? What sort of velocity spreads were you getting with the same charge? I ask because that could be an indication of a concentricity issue. Here is a link to some discussion.

http://68forums.com/forums/showthread.php?52419-Concentricity-Gauge

Also, take what you think is your best/optimum charge weight and adjust COAL in 0.010" or 0.015" increments down to around 2.26". COAL can be as powerful as powder charge in tuning your loads.
 

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Both my 11 and 13 year old daughters shot deer with factory Full Boar out of an 18" ARP. The 11 year old put it dead center on the neck and rolled her 14in 8pt over backward. The bullet ended up in the liver, but it carved a 12 in long 2in diameter hole thorough the neck. It expanded just like the ones they show in the ads.

The 13 year old shot a 17 1/2in 9pt quartering toward and the bullet went in center lung came out the low back guts and through and throughed the rear leg. He hobbled a couple steps, and turned around and she gave him a second dose, double lung from the opposite side. Just under the initial shot shoulder it looked like a golf ball went it the rib cage, I have pics of that somewhere, I'll look when I get home.

Very impressed with the damage of the gmx, and they only had one get away with SSTs. Between the 2 of them they have shot 5 deer with the 6.8s in the last 2 years.
 

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re

Both my 11 and 13 year old daughters shot deer with factory Full Boar out of an 18" ARP. The 11 year old put it dead center on the neck and rolled her 14in 8pt over backward. The bullet ended up in the liver, but it carved a 12 in long 2in diameter hole thorough the neck. It expanded just like the ones they show in the ads.

The 13 year old shot a 17 1/2in 9pt quartering toward and the bullet went in center lung came out the low back guts and through and throughed the rear leg. He hobbled a couple steps, and turned around and she gave him a second dose, double lung from the opposite side. Just under the initial shot shoulder it looked like a golf ball went it the rib cage, I have pics of that somewhere, I'll look when I get home.

Very impressed with the damage of the gmx, and they only had one get away with SSTs. Between the 2 of them they have shot 5 deer with the 6.8s in the last 2 years.
Congrats to your girls !
I would really like to see the pics and details of the shots,range etc.

Also what were the circumstances of the one getting away with the SST ??
That concerns me as I am planning on using the Hornady 120 SSt factory loads out of an 16 and an 18 inch ARP upcoming season.
 

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The one that got way was a flinch on the younger ones part, no fault of the bullet. The SST is a great bullet, we tried the GMX after my older daughter shattered the spine on one, and I found some bullet fragments in the backstraps.
The bullet is from my younger daughters deer at about 75 yards.
The carcass pics are from the 9pt shot at about 40 yds. You can see the entry hole at the top of the shoulder, the second pic is with the shoulder removed, entry side into the ribcage.




 

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The one that got way was a flinch on the younger ones part, no fault of the bullet. The SST is a great bullet, we tried the GMX after my older daughter shattered the spine on one, and I found some bullet fragments in the backstraps.
The bullet is from my younger daughters deer at about 75 yards.
The carcass pics are from the 9pt shot at about 40 yds. You can see the entry hole at the top of the shoulder, the second pic is with the shoulder removed, entry side into the ribcage.




That looks like great bullet performance ,that is a nice hole in the ribcage.I am assuming the bullet exited on the 9pt?
 

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Load development for 100 gr GMX

I have been working up a load with Accurate 2230 since A2200 has so far been unavailable where I live in Central MN. I am hoping to use these bullets for deer hunting this fall. I am shooting a 20 inch ARP barreled upper on my MMR lower. I started loading at 28 gr and am up to 30 gr with no pressure signs. I am loading at a coal of 2.295.
So far I have achieved a high of 2647 at 30 gr. Accuracy has been OK but nothing to shout about. My best group so far was with 28.5 gr and was around 1.35". All testing has been at 100 yds. Most of my shots to be had where I hunt will not be over that distance. I have 3 more batches of cartridges loaded up for testing. 30.2, 30.4, 30.5 gr each. My brass catcher has been invaluable as it seems I have found another cartridge that I like where the brass has a cost more similar to gold. I will post more results when I am able.
 

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UNSavage, I found I can save a lot of bullets by doing single powder charge per shot velocity ladders to determine where my max limit is. The closest I load them is 0.3 grain increments, e.g, 28.7, 29.0, 29.3, 29.6, 29.9, 30.2, 30.5, etc. Track your velocity as you shoot the ladder looking for a straight line progressing of velocity increase. If you get a larger jump or velocity flattens off, this is another clue that pressure limits/efficiency has been reached. This way you don't expend a lot of time and rounds finding your performance limit. if you are lucky, you can get an indication of your accuracy node also. Mark each impact. If you get 3 in a row that group under an inch, the middle one is where you should find your accuracy node - verify with a 3-shot group. Sometimes, I'm in the field hunting with a new load in less than 10 bullets. Adjusting COAL in 0.015" increments is another way to tune a load if you are looking for additional accuracy. All the best.
 

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Thanks for the advice. I have been loading 3 rnd batches is all. I enjoy the shooting part of load development but I could speed it up bit with your method. I will give it a try with the box of 95 gr ttsx I have. From what I have seen on the Western powders load data I should be maxed by 30.5 gr with the 100 gr GMX so I wanted to approach it in smaller increments. I forgot to mention in my first post that I am using Federal once fired brass and CCI 450 primers.
 

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UNSavage, the load data the publish is for SPC plus they don't cover the 100 GMX specifically from the data I looked at. SPC 2 often can go a little higher (55,000 vs 58,000 psi) but it looks like all their max loads were compressed which indicates that case capacity is the limiting factor. You might try a drop tube if you don't have any more room left and you still aren't seeing pressure signs to get additional powder in the case.

http://68forums.com/forums/showthre...Magazine-COALs&p=508826&viewfull=1#post508826
 

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Started to see flattened primers at 30.8 gr of 2230. Chronograph read 2701 fps. This was the tightest 3 shot group at right around an inch. Xman I will be making a drop tube. I have plenty of arrows leftover that I can no longer use thanks to a shoulder injury that will not let me draw my bow. Thank goodness it does not affect my rifle shooting......much. 30.8 make a little crunch when seating but I was still able to seat at 2.295. My mags will let me go just over 2.30 so I may try the longer seat and see if I can get a bit better than 2700.
 

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30.8 make a little crunch when seating but I was still able to seat at 2.295. My mags will let me go just over 2.30 so I may try the longer seat and see if I can get a bit better than 2700.
UNSavage, 2700 fps with AA2230 and 1 MOA accuracy. That is better than factory Full Bore. Sounds like you are good to go.
 
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