6.8 SPC Forums banner
1 - 15 of 15 Posts

·
Registered
Joined
·
8 Posts
Discussion Starter · #1 ·
Have seen this start showing up online for sale. Anybody have a chance to shoot any yet? Wondering what the "real world" velocity on this is , would be nice if it is faster than advertised speed. Would appreciate any ones hands on opinions on this new round....Joe
 

·
Registered
Joined
·
4,803 Posts
I have some 100 CX components coming next week to test and checkout. The 100 GMX it replaces was an excellent copper bullet, expanding well and holding together even in-close. I want to find out what has changed. I read an on-line review that claimed the 100 CX was fragmenting on them. Hornady also list the BC (G1) of the 100 CX (0.262) lower than the GMX (0.310). I measured the GMX's BC at 0.297 with a LabRadar. I should have a report out in a couple of weeks.
 
  • Like
Reactions: Hobbes96

·
Registered
Joined
·
8 Posts
Discussion Starter · #4 ·
I have some 100 CX components coming next week to test and checkout. The 100 GMX it replaces was an excellent copper bullet, expanding well and holding together even in-close. I want to find out what has changed. I read an on-line review that claimed the 100 CX was fragmenting on them. Hornady also list the BC (G1) of the 100 CX (0.262) lower than the GMX (0.310). I measured the GMX's BC at 0.297 with a LabRadar. I should have a report out in a couple of weeks.
Thanks Xman, will be looking forward to that...Joe
 

·
Registered
Joined
·
4,803 Posts
I will not be able to help with factory ammo mz. But here is comparison: 100g GMX on the left and CX on the right. The external profile measured the same for both versions. The CX appears to have the new heat/friction-resistent tip material that Hornady is using plus there is only a single instead of two pressure-relieving grooves. You can't see it in the image but there is a slight impression in the CX's bullet shank, like it was removed from a mold. I communicated with Dave Emary back when the GMX was introduced, and he advised that more than two grooves (like Barnes bullets) did not provide significant additional pressure relieve. Interesting that Hornady made the effort to remove the second groove. It will be a couple of weeks before I can complete range testing with the bullets.

Wood Cone Street fashion Ammunition Gas
 

·
Registered
Joined
·
447 Posts
I will not be able to help with factory ammo mz. But here is comparison: 100g GMX on the left and CX on the right. The external profile measured the same for both versions. The CX appears to have the new heat/friction-resistent tip material that Hornady is using plus there is only a single instead of two pressure-relieving grooves. You can't see it in the image but there is a slight impression in the CX's bullet shank, like it was removed from a mold. I communicated with Dave Emary back when the GMX was introduced, and he advised that more than two grooves (like Barnes bullets) did not provide significant additional pressure relieve. Interesting that Hornady made the effort to remove the second groove. It will be a couple of weeks before I can complete range testing with the bullets.

View attachment 76414
That CX tip does look a little more aerodynamic. Be interesting to see what your testing shows. Thanks in advance!
 

·
Registered
Joined
·
4,803 Posts
I completed a quick check of the CX this morning for BC and terminal performance. Besides the CX's new heat/friction-resistant tip and single groove, notice that the groove is a radius indentation which also helps improve BC compared to a square cut. With an average muzzle velocity of 2706, the measured BC (G1) was 0.303, significantly more than the advertised BC of 0.262. This is a slight improvement over the previous 100 GMX version that measured 0.297 today, consistent with the BC measured in 2017. The GMX may have 10 to 20 fps advantage in muzzle velocity with the same powder charge as the CX due to having two pressure relief grooves instead of one.

More important, is the CX's terminal performance. The range was busy with activity, so only a quick comparison test was conducted between the GMX and CX with an impact velocity of 2510 fps for both bullets. Initial indications are the bullet performance of the CX may expand more than its predecessor. Both expanded to 0.5 with an insignificant difference. However, you can see from the picture that the CX expanded further into its expansion cavity shortening from 1.125" to 0.455" compared to 0.500" for the GMX. The CX may have refinements to its expansion cavity or be made with a softer grade of copper. Further testing will be needed to quantify the differences but for now, it appears the CX will have similar performance to the GMX it replaces.

Hornady was contacted to suggest they double-check the BC data for the 100 CX. More to come.

Plant Nature Organism Mammal Happy
 

·
Registered
Joined
·
1,869 Posts
While not a completely flat face it appears not to be as round as some other bullets which in my opinion will help it to make better exit wounds and keep it on course through the body .

Sent from my LM-K920 using Tapatalk
 

·
Vendor
Joined
·
2,388 Posts
While not a completely flat face it appears not to be as round as some other bullets which in my opinion will help it to make better exit wounds and keep it on course through the body .

Sent from my LM-K920 using Tapatalk
I agree.
CBB's do an even better job than a bullet that flattens out because we actually have a dish in the middle once expanded. In addition to 3 petals with massive expansion.
Thats one reason I went with 3 petals instead of 4. The other is 3 petals have better petal retention and if they do come off larger pieces to create more trauma.
 

·
Registered
Joined
·
108 Posts
Does anyone have chronograph or field velocity data from the new factory Hornady 100gr CX ammo?

I have a hard time believing 2550 from a 24" barrel is accurate, given that would likely equate to ~2400 from a 16" barrel, which is beyond anemic for a 100gr bullet (and a divergence from Hornady's typical velocity trends).

2550 from a 16" barrel would make more sense, perhaps they underloaded the cartridge to keep the bullet intact at normal hog distances. It's still too slow.
 

·
Registered
Joined
·
4,803 Posts
Oregun, Hornady screwed up their BC listing showing 0.262 when it is really 0.303. Even 2550 from a 16" barrel is not pushing the pressure limits so their MV listed could likely in error and their barrel length certainly is. I was getting 2700 fps from a 14" barrel without pushing it. The ballistic table they list on their website may even have errors in their down-range velocity for a 0.262 BC. Some employee certainly rushed inputting the data to meet a press deadline. I wouldn't let their publishing errors stop you from trying a box or two.
 
  • Like
Reactions: BobKaro

·
Registered
Joined
·
108 Posts
Thanks Xman,

I agree it's probably wrong, thank you for your testing.

I'm most interested in their factory loading - .303 BC with a 100gr all-copper is a fantastic general purpose option, and an alternative to the MIA 110 PTS. At $1.50 a round it's competitive, as long as they've loaded it above 2700. For handloading, the 105 MKZ makes more sense at the same price (higher bc, better terminals).
 
1 - 15 of 15 Posts
Top