My love for this round is fading

[LRRPF52]

Good to hear. Wanna change your thread title now?

[1911man]

Exactly, i should change it to my love for this round is growing.

[LRRPF52]

I put my toe in the water with the 6.5 Grendel back in 2009, but had been closely watching it develop since 2004, when a good friend of mine who was an SF Sniper instructor at Bragg said that his Grendel was the most accurate rifle he owned, and he owned enough rifles that he lost count of them.

It was still a wildcat back then, with no SAAMI approval or submission even, and it looked like SAAMI approval would be long off, if ever. I didn't care because I hand-loaded, so not a big deal I thought. Initial velocities I saw were nothing to write home about, because I was using one of the Vihtavuori powders. I was shooting with a quick change barrel upper, and accuracy was maybe 1.2 MOA. I was still fixated more on velocity at the time, and realized that I needed to work more with the cartridge to see what I could get out of it.

Once I built a dedicated upper for it, and shot some Precision Firearms 123gr Scenar loads, I started seeing .75 MOA accuracy, and 7fps ES. Hornady came out with the 123gr A-MAX load, so I started shooting that to see what it would do, and it was very accurate as well. Hornady also submitted it to SAAMI, and things started happening quickly.

After trying 8208XBR, TAC, and CFE, I saw speeds that were impressive for a 16" barrel pushing 100-129gr pills, and I began to let my nephews and new shooters use the Grendel for shooting steel targets at long range for fun. I figured it was a 700yd at best capable system with the 16" barrel, until some guys challenged me to hit a 1200yd target one day out at one of my shooting areas. I was surprised at how easy it was to place round after round on target at that range, after dialing the elevation my program told me, using 123gr A-MAX box ammo.

I started bringing the Grendel to my DM Courses, where a lot of people either bring 16-20" AR15's, and a few AR10's in .308. The AR15 is great for being able to recover quickly from recoil and watch your impact, but the energy on target is anemic, and wind deflection is significant with even the 77gr SMK. The .308's hit nice and hard, but recoil takes you off target, and starts to fatigue shooters quickly.

I was running one closed military course, and the whole time I was thinking, I wish I had my Grendel here right now. We had steel popper targets that fall when hit. At 200m, the 5.56 needed a hammer (quick 2-round) placed on the head to knock them over(exceptionally toilsome to to pull off), whereas the 7.62 NATO sent the target and its base tumbling over the backside of the berm. At 300m, it was extremely difficult to get the poppers to fall with 5.56, except for one 24" barrel gun a guy brought, and the 7.62 NATO had no problem knocking it down of course. I started bringing my 16" Grendel to my courses, and have added the 18" Grendel as well. You get the handling of the AR15, with 80-90% of the impact of a 7.62 NATO, but without the recoil.

The cartridge definitely has grown on me.

[lamrith]

That is great news 1911Man!! Glad your staying with the Horde, we are the cool crowd anyway, so you will have mroe fun as part of it than an outsider :-p

LRRPF52 - you keep posting like that and I might have to build another one, STOP IT!

[pdq5oh]

1911man, this target is 5 shots at 100 yds. The top one is 27.8gr 8208, 123 SST, 2.250" OAL. Av: 2,446 ES: 52.2. SD: 21.8. Not good velocity variation, IMO. It may have been changing light conditions over my chrony? Variable clouds, sun. I somehow managed to drop one shot out of the cluster.
Bottom target is 5 shots. 28.1gr 8208, 123 SST, 2.250" OAL. Av: 2,473 ES: 37.9 SD: 16. A little better. Before I shot, I moved my scope a couple clicks left, instead of right. DUH! I moved it back right and put 3 in the X. The shot high right is my fault. I was taking too long to break the shot and tried to bail but couldn't stop the squeeze. Lifted my head to blink my eyes & made a bad shot. So 3 were good shots. I hope to shoot them at 500-800 this weekend and see if they group at those ranges.
I tried some at 28.3 but was compressing the powder and didn't feel any velocity gain would be worth it. AMAXs loaded the same didn't shoot as well at 100 and were a little slower.
Re: my poor results with ES & SD. I weigh each charge to the tenth of a grain on a digital scale. I let the charge sit a few seconds to let the scale settle to avoid drift. I'm full length sizing with a Hornady Custom die. Seating bullets with a Hornady Custom die. I measure each round to be sure OAL is the same to within 1.5 thou. There's about .006 neck tension. Could this be a neck tension issue? Do those of you reloading clean and lube the case necks before seating bullets? I've read pros and cons of cleaning the necks. All brass is sonic cleaned before reloading. Primer pockets are cleaned. Even though these shoot well at 100, I'm afraid they'll group poorly out past 500 due to velocity variations. Or are the variations in velocity what I can expect with a gas gun? Should I suspect a crony problem? Any insight and advice will be greatly appreciated. Thanks in advance.

[1911man]

1911man, this target is 5 shots at 100 yds. The top one is 27.8gr 8208, 123 SST, 2.250" OAL. Av: 2,446 ES: 52.2. SD: 21.8. Not good velocity variation, IMO. It may have been changing light conditions over my chrony? Variable clouds, sun. I somehow managed to drop one shot out of the cluster.
Bottom target is 5 shots. 28.1gr 8208, 123 SST, 2.250" OAL. Av: 2,473 ES: 37.9 SD: 16. A little better. Before I shot, I moved my scope a couple clicks left, instead of right. DUH! I moved it back right and put 3 in the X. The shot high right is my fault. I was taking too long to break the shot and tried to bail but couldn't stop the squeeze. Lifted my head to blink my eyes & made a bad shot. So 3 were good shots. I hope to shoot them at 500-800 this weekend and see if they group at those ranges.
I tried some at 28.3 but was compressing the powder and didn't feel any velocity gain would be worth it. AMAXs loaded the same didn't shoot as well at 100 and were a little slower.
Re: my poor results with ES & SD. I weigh each charge to the tenth of a grain on a digital scale. I let the charge sit a few seconds to let the scale settle to avoid drift. I'm full length sizing with a Hornady Custom die. Seating bullets with a Hornady Custom die. I measure each round to be sure OAL is the same to within 1.5 thou. There's about .006 neck tension. Could this be a neck tension issue? Do those of you reloading clean and lube the case necks before seating bullets? I've read pros and cons of cleaning the necks. All brass is sonic cleaned before reloading. Primer pockets are cleaned. Even though these shoot well at 100, I'm afraid they'll group poorly out past 500 due to velocity variations. Or are the variations in velocity what I can expect with a gas gun? Should I suspect a crony problem? Any insight and advice will be greatly appreciated. Thanks in advance.

Phil,

That top group looks very good, have you measured it? Its looks sub 3/4 MOA easy from the picture. As far as your velocities go I have had days like you described where rolling shade has messed with my chronograph numbers. That is why it is important to get large samples, just just relying on 5-10 shots wont give you the whole picture. If you can chronograph at least 20 rounds and even better make separate trips to see if you might be getting some off numbers from day to day it will paint a better picture for you. How many rounds did you shoot over the chrono to come up with the numbers posted? My gut reaction is that if you have that wide of a spread you have not found your optimum charge weight yet. I wouldn't be afraid of compressed loads as long as you are working your way up and staying within advertised limits. I believe the max load for 8208 and a 123 amax is 28.5 but check your manual. You could also try the 120 smk as I have found it to be a very forgiving and accurate bullet. I am using the same dies your using and I clean my brass with a sonic cleaner, full length re-size, trim to 1.516, then de-chamfer the mouths and necks of the case and start loading. It has been a while since I looked at the numbers for neck tension so I hope someone else can chime in with that info. What barrel are you using and what length?

[pdq5oh]

The 4 shots measure .540-.264=.276. All 5 measure .732-.264=.468. The bottom 3 shot target measures .468-.264=.204. These are measured with my caliper, not a program. The barrel is a 20" Black Hole, 1/9 twist.
I was looking thru all my data to this point and have never had real good, low ES & SD numbers. My .223s shoot my reloads well. I guess I'll see how the Grendel shoots past 500 and not worry if I get satisfactory results. Thanks.

[1911man]

Phil, have you tried any other powders? Slot of guys on here are having great success with cfe 223. My rifle seems to hate it but I am going to try out some new loads with it. My rifle loves TAC and the 120 smk. I have the 18" version of your same barrel. You just have to find the right combo.

Edit. If it's grouping well I would not worry to much about the spreads. I use chrono data to help with dope for long range shooting and to help me tell if my loads are over pressured.