Hornady GMX

[snuffy]

I got in a mood to do a little expansion testing. The Hornady GMX interested me in that it wasn't pure copper, so it would be less likely to copper foul the barrel.

This is hardly the first time I've done this sort of thing. Back in 2002 I did some tests on the then new Hornady interbond. Anyway, here's some pics of 2 recovered GMX bullets fired from my Browning A-bolt 300 wsm;











Now aren't those some beautiful mushrooms? Expansion is .615 and .640, retained weight is written on the paper in the bottom pic. Which is the absence of the plastic tip for one and maybe the loss of some of the metal and the tip on the other.

The story behind this bullet is that it is built from gilding metal, the same stuff most jacketed bullets use for their jackets. Therefore it's like shooting any other bullet, as far as the fouling goes.

I loaded these with my favorite powder for my 300 WSM, H-4831 SC. I choose a mid range load, Lyman 48th said start at 65.0 to 72.0,(for 165's), I went with 68.5, loaded 15 for testing. I forgot to write down the chrono readings, but remember 3000+ for two rounds.

These were fired into water filled gallon milk jugs laid on their sides, one behind the other, @ 100 yds. The first three were lost in the grass, the bullets kept skipping out the side of the 3rd jug. Finally 4 and 5 were captured. One came to rest in the third jug, one barely made it into the forth.

The first jug was mostly blown into 4 pieces, the second was split wide open, the third simply had a hole through with the bullet laying in the bottom, the one that made it to the forth barely made a slit in the bottom.

[Doodlebugger45]

Those are indeed beautiful looking bullets. I for one am not familiar with the GMX. Would they be significantly different than the Barnes X Bullets? And this is purely a gut instinct question, but do you think they would expand as well with reasonable .308 velocities, which are a bit slower than your rifle?

[snuffy]

Good question doodleB. I also have a .308, maybe I'll try some to find out! The plastic tip should start expansion at lower velocities, whether or not they would expand as big would be what I'd like to find out.

[snuffy]

Another range trip today, this time was all handgun shootin. Had some jugs left, AND some water, so I devised a small test using some HP s-auto rounds. First came my SA 1911 45. I got some 185 XTP Hornady's some time back loaded them with 6.9 231.

I lined up 4-1 gallon milk jugs filled with water. Good thing I used 4 for the 185 XTP! Bullet was inside the fourth jug!







That's the 185 45 XTP on the right. It expanded to .550 and penetrated 3 jugs to end up in the fourth.

Left bullet is a speer gold dot 40 S&W in 165 grain weight. It expanded to .656, and stopped in the second jug! At least the first one did---since I had four jugs end to end. that meant I had 2 left. Soooooo I lined them up and shot again. Welllllll that time the bullet penetrated the second jug to be lost in the berm.

My take on this is I was disappointed in the performance of the XTP. I would expect it to expand further. I was pleasantly surprised in the gold dot's expansion, AND the weight retention! However 1 bullet of each proves almost nothing as far as statistics are concerned.

Maybe this will interest more people than the rifle test!???¿

[snuffy]

Maybe this will interest more people than the rifle test!???¿

But then, apparently NOT! I guess I'm wasting my time.

[Luciano]

Good stuff snuffy! Thanks for taking the time to do this. I also like how you describe the procedure. Yeah, XTP looks a bit disappointing but like you said it might not mean anything since was only one bullet. Got a .44 mag for testing?

[snuffy]

Yeah, XTP looks a bit disappointing but like you said it might not mean anything since was only one bullet. Got a .44 mag for testing?

As a matter of fact I do! And some 240 XTP's loaded too. I might just throw the super blackhawk in the range bag next trip!

[Maligator]

Nice work Snuffy, I just purchased a new Tikka T3 Hunter in 300WSM and have been looking around to see what people say about round choices and powder combos.

Before the gang all jumps in...yes I have my own manuals and plan on following them; its just nice to see results others have achieved with their selections.

[Randy 1911]

What was they shot into? Beautiful expansion.

[snuffy]

What was they shot into? Beautiful expansion.

Water.

These were fired into water filled gallon milk jugs laid on their sides, one behind the other, @ 100 yds. The first three were lost in the grass, the bullets kept skipping out the side of the 3rd jug. Finally 4 and 5 were captured. One came to rest in the third jug, one barely made it into the forth.

[bgdv1]

could the hornady 168gr AMAX (30 cal)bullet be used for white tail hunting or is it a target bullet ?

[snuffy]

The A-max Hornady is a target bullet period. Could it be used to hunt whitetails "in a pinch"? Yes but clearly not the best option. It may expand, it may not expand, it might blow up and fail to penetrate.

[bgdv1]

ok thanks for the info.

[Stick_man]

I see other manufacturers are finally catching the vision that Barnes had many years ago. Hornady is playing the copycat game again with these (think of the vMax compared to the Ballistic Tip) These look pretty good, but are really only for the magnum rifles if you want any expansion at all. I have seen the TSX and TTSX expand very well at velocities much lower than the 2700fps that it takes to expand the GMX. I would also bet the Barnes offerings don't foul the barrels any more than the GM, mainly because of the reduced surface contact. I would also suggest that the Barnes will have lower pressures for the same given velocities as the GMX.

However, I would not be opposed to trying those GMX out to see how they work in MY gun. I could be wrong about all this, but I have personal experience with the Barnes TSX and have been verrrry happy with little if any barrel fouling and exceptional accuracy and expansion.

Good luck with them and let us know how they go.

[freakshow10mm]

Snuffy, don't get excited about the XTP expansion. The XTP was designed as hunting bullet from the get go and thus is primarily designed to penetrate deep, then expansion being secondary in importance.

Live animal testing over a few years using a 10mm and 357 Magnum on deer, black bear, and coyote resulted in consistent expansion just about 160%-170% and penetration as deep as you need.

I'm really interested in the GMX as I was going to add a .308 load to my ammunition line but haven't had the time to develop a load so I haven't bought any bullets yet. I wish they made a heavy (70-80gr) .224 GMX bullet. I've decided to take the plunge and built a custom rifle in .224 TTH.

[snuffy]

I see other manufacturers are finally catching the vision that Barnes had many years ago. Hornady is playing the copycat game again with these (think of the vMax compared to the Ballistic Tip) These look pretty good, but are really only for the magnum rifles if you want any expansion at all.

Well, that's your take on Barnes. I will never load a barnes bullet. Too expensive and they DO foul more than any other mono expanding bullet. Their cutting grooves in the bullet to reduce fouling is one answer. Nosler's E-tip is another copycat?

The plastic tip ensures at least some expansion. The E-tip and GMX are simply hollow point bullets with a plastic wedge in the cavity. This initiates expansion. Hollow point bullets have a tendacy to "plug", failing to expand.

I plan on a mild load in .308 to simulate a GMX hitting at 500 yards from a magnum rifle. A .308 starting load will result in around 2100 fps at the muzzle. That's about what the GMX would be doing @ 500 yds. from my 300 WSM.

[impalacustom]

Stick Man I see what your saying about the less pressure and bands in the Barnes but there are only 2 companies that truly figured out driving bands on bullets and neither one is a US company and both are very expensive. One is in Germany and the other is in South Africa, and they both are solids made from copper.

I personally don't have experience with Barnes but I've seen my uncles 460 Weatherby shoot the Barnes solids and lets just say fouling was so bad after 3 shots it looked like the barrel was copper lined.

I have had lots of good luck with the XTP in 300gr in my 44 magnum they expand nicely but as Freakshow I've never shot them in anything but animals. I might have to try some in milk jugs or something though now.

Snuffy, keep us informed, I am curious especially since I am close to Hornady and keep trying to bribe them to make some new bullets.

[snuffy]

I may as well NOT do the above mentioned experiment. Click on this link, then click on GMX tm ammo and bullets.

http://www.hornady.com/story.php?s=785

Expansion @ 2000 fps is minimal in ballistic gelatin. I doubt that water would result in much more expansion.

These look pretty good, but are really only for the magnum rifles if you want any expansion at all. I have seen the TSX and TTSX expand very well at velocities much lower than the 2700fps that it takes to expand the GMX. I would also bet the Barnes offerings don't foul the barrels any more than the GM, mainly because of the reduced surface contact.

Stickman, you obviously already looked at that video on the Hornady site. BUT I'd bet that even that little bit of expansion would be enough at long range, or close up with a .308.

Here's noslers version of a tipped monolithic bullet, the E-tip.

http://www.nosler.com/etip.htm

They simply say it's of a "special"210 alloy, NOT pure copper. They also claim that it expands down to 1800 fps. I don't see any bands cut into the sides of the bullet, and the almost visible boat tail doesn't act to limit bearing area,(like the sharp boat tail on the GMX). I wonder how the fouling is on the E-tip.

[snuffy]

Here's another write-up on the GMX.

http://www.hornady.com/story.php?s=792

Looks like 2000 fps just starts the nose to disrupt. I may STILL do my own test just to see what kind of penetration occurs at that velocity.