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View Full Version : .308 150gr Blemished GMX load??


gottarollwithit
05-05-2010, 11:12 PM
Anyone buy into MidwayUSA's offering of .30 cal lead free/copper solid 150 gr bullets a couple of weeks ago??

They're lead free, 150 gr, and have red polycarbonate tips, so they've got to be Hornady GMX projectiles - there's no other lead free projectiles that resemble these...

Anybody have a good load for these things using Varget or 4895?? I've noticed that the tips aren't all on straight. Some of the tips look bent or crooked... Isn't this a big problem in terms of projectile stability and accuracy? These things almost look as if they were pulled down from something b/c they're pretty dirty...

Thanks!

gottarollwithit
05-07-2010, 3:07 AM
Hmm, i'm surprised nobody here wanted to get in on the cheap lead free bullets..... It is afterall Cali with the silly lead free hunting laws...

FLIGHT762
05-07-2010, 7:05 AM
I bought 2 boxes of the Hornady GMX 130 gr. 270 bullets to reload in my 270 Win.

I have a L/H Tikka T-3 stainless that shoots my various handloads within Tikka's 1-MOA accuracy. Almost any 130 gr. bullet shoots well in my rifle with 56.0 gr. of IMR4831.

I loaded and tested the GMX's using 3 different powders(including 56.0 IMR4831, it shot the worst). I got 3" to 5" groups at 100 yards. I shot about 20 rounds.

I re shot the rifle with one my other handloads and it shot the normal 1-1.5 MOA.

A few months ago,I bought some Barnes 130 gr. .270 TSX bullets and loaded them using 56.0 of IMR4831. They shot well within 1.5 MOA.

I contacted Hornady a few days ago and I will be sending them 10 or so of my 130 gr. GMX's for them to test. I was very disappointed in my GMX's. I hope Hornady will come to the same conclusion as I did with this lot of GMX's. I was looking forward to using them for hunting.

I hope you have better luck with yours than I did.

gottarollwithit
05-07-2010, 8:40 AM
So were the poly carbonate tips crooked to some degree?

It looks crooked enough to affect the aerodynamics of the projectile when spinning at high RPM and moving fast.

Fjold
05-07-2010, 12:50 PM
Bullets steer with their bases.

mycrstuff
05-07-2010, 7:24 PM
The blem bullets are the GMX. When I ordered mine I did a search of the mfg code on the Midway site and the regular priced GMX bullets came up. The regular ones were 3 times the price.

I did some searching and you can use the load data for the Hornady Interbond (IB) and SST bullets. Varget is listed in the Hornady manual but 4895 is not. You could try loading the 4895 using the Garand load listed.

I am going to try 4064 as it allows for 2900 fps without it being the max load. The GMX needs a fast speed to fully deform upon impact. I might also try Win 760 as it will also push it at that speed. The 760 takes 5 grns more of powder to reach the same speed. That may make it hard to seat the bullet as the case will be completely full. I have an 8 lb of 760 that I don't want to open up until I know if the powder will fit. If anybody tries it let me know. If not I will use up the 1 lb of 4064 first.

gottarollwithit
05-07-2010, 10:59 PM
I haven't measured these bullets with calipers yet, but supposedly they're rather long for being 150's. This might present a prob for you with your 760.

I want to use this in my .308 as a hunting cartridge. However, i think i'm going to have trouble pushing this thing fast enough to really make it useful. It needs to be around 3000fps to get decent deformity, but i think in a 308 the most i'll be able to squeeze out of it is maybe around 28-2900.

I guess i'll use some surplus 4895/4064 stuff and start at 43 gr, then work it up to maybe 46gr? I'll chrono it and crank up the heat on this stuff in a few months.

mycrstuff
05-08-2010, 12:05 AM
According to Hornady that will be a hot load. I cross referenced the Speer manual and they load much hotter. The Hornady manual might be cautious as most people just load to the max without testing the load.

Go ahead and try it out. Hopefully you live closer to the range than I do. It is an 1 1/2 drive for me to get to the nearest range. I wish I could load up a few rounds and then test them. Unfortunately I can't do that without a long trip. What I need to test rounds is a van with a reloading bench inside so that I can reload at the range and then step outside and chrony the loads.

gottarollwithit
05-08-2010, 5:10 AM
What exactly does the Hornady manual say regarding 308 with 150 gr GMX/SST/IB when using 4895, 4064, or Varget??

I looked around online and couldn't find any solid info. I figured these things were pretty close to 150gr BTFMJ which is in the IMR load database, and took charge values off that.

My prob is that it takes me months to find time to handload and range test. The range is only a few miles away too!

bcrich
05-08-2010, 6:48 AM
What exactly does the Hornady manual say regarding 308 with 150 gr GMX/SST/IB when using 4895, 4064, or Varget??

I looked around online and couldn't find any solid info. I figured these things were pretty close to 150gr BTFMJ which is in the IMR load database, and took charge values off that.

My prob is that it takes me months to find time to handload and range test. The range is only a few miles away too!

My 7th edition doesnt show gmx but it shows sst/ib....for 4064 & varget it shows 44.9g for both powders as max going 2700fps, 4895 (imr) shows max at 46.4g going 2800fps. coal for both test loads show 2.735. good luck

gottarollwithit
05-08-2010, 12:31 PM
Awesome, thx for the data.
The stuff i'll be using has a 4895 burn rate, but 4064 powder size/density. I guess i'll stop at 46 or whenever the compression gets too scary, which likely will be around 44-45.

How does everybody else use these GMX bullets their full potential in a 308???
They need to be pushed up to like 3000FPS to really work, but most max loads top out at around 28-2900fps. Does everyone just use these for a 30-06, or run cartridges that aren't working at their full potential?

Thanks!

ethanasmith
11-08-2010, 4:59 PM
I also had problems with Hornady .270 GMX rounds, though mine were factory loads (130 gr). I bought three boxes, and the first box and a half flew all over the paper, despite a bench rest and spotless barrel. I was surprised, as this rifle (old style Weatherby deluxe) has been a consistent 1" grouper with Barnes TSX and any other primo bullets. I thought maybe my scope was loose, so I threw in some cheap old Federal soft-nose bullets and they stayed within around 1.5" as a group. Don't know if it was a bad batch of bullets, bad loads, or what.....but I'm certainly not buying more until I talk to the Hornady Reps and see if the problem is fixed.

FLIGHT762
11-08-2010, 7:12 PM
As an update on my post(#3), I did send 15 bullets to Hornady. They loaded up 10 rounds using 46.5 IMR 4064. They got 2- five shot groups that shot MOA with their rifle. The tech even called me at home to report their findings. He was very polite, but couldn't do anything for me. He sent me a free Hornady hat. :rofl2: My Tikka just doesn't like them.

The Barnes TSX 130s shoot well out of my rifle. When I went to Cabela's in late May, They had a sale on the .270 130 TSX bullets for reloading. $22.00 a box! I bought 5 boxes. That will give me enough for a few years.