I've been comparing ballistics of the best long range loads out of 20" barrels for both the 223 and Grendel. I doubt I will ever shoot to 1000 so I am keeping the max at 800.
What do you guys use as your best long range load (not single feed loads)now that the 77TMKs are out and is there really any need to consider the Grendel?
The 77TMK is expected to test out very close to the claimed BC of .420 while the tested BC of the 123SST and Amax is .462. Out of 20" barrels the 223 can send 77s down range apx 200fps faster than the grendel can shoot 123s and from my calculations the 123s can never catch up.

I'm interested as well. I'd imagine rost495 may have some input.

The Grendel will be the better performer at distance. The .223 may be faster out of the gate, but when it dies, the higher BC of the 123gr Grendel will keep it going. The Grendel will also buck the wind better.

I haven't tried any TMK's yet (feel free to send me some ), but will be testing some 77's and 75's this weekend at 600 yards.

no clue these days. I'd still run 75 amax at mag lenght. LOL

I hear the 77 tipped are really not easy to get to shoot well....

I'd think that there is no way for the 223 at mag length to catch the grendel personally.

I shot the grendel for Arne some when it was still 6.5 ppc, and I was shooting 90 jlks in the 223 single load at the time. In the wind at 600, my impression vs the 90s is that the grendel had it hands down vs wind drift... Mind you that might have only been a solid 3-6 inches less at 600 but it was noticeable to me...

I forget what we shot... 120 something lapua iirc in the 6.5ppc vs my 90s

I have already run the numbers and it appears to me the 223 beats the Grendel easily. During testing we were able to get the 77s up to 2850 using CFE but I used 2750 for this comparison. BTW I am using a short throat chamber in a Krieger to get the 77TMK to shoot. We are using the LBC chamber for the 6.5. It shoots better than the Grendel chamber but still does not like the 123 Sierra or Lapua. Will shoot the amx under 1/2" Limited to a 300yd range at the moment.
223-179" drop and 62 drift at 800.
6.5-217 drop and 64" drift.
Calculated Table
Range Drop Drop Windage Windage Velocity Mach Energy Time Lead Lead
(yd) (in) (MOA) (in) (MOA) (ft/s) (none) (ft•lbs) (s) (in) (MOA)
0 -1.5 *** 0.0 *** 2857.2 2.535 1395.5 0.000 0.0 ***
100 1.7 1.7 0.7 0.7 2646.0 2.348 1196.9 0.109 19.2 18.3
200 -0.0 -0.0 3.0 1.4 2444.4 2.169 1021.4 0.227 40.0 19.1
300 -7.6 -2.4 7.0 2.2 2251.7 1.998 866.7 0.355 62.5 19.9
400 -22.0 -5.3 13.0 3.1 2067.7 1.834 730.8 0.494 86.9 20.8
500 -44.6 -8.5 21.2 4.1 1892.8 1.679 612.4 0.646 113.6 21.7
600 -76.9 -12.2 32.0 5.1 1728.0 1.533 510.4 0.812 142.8 22.7
700 -120.9 -16.5 45.5 6.2 1574.7 1.397 423.9 0.993 174.9 23.9
800 -179.0 -21.4 62.2 7.4 1434.9 1.273 352.0 1.193 210.0 25.1

Grendel -123 Amax
ulated Table
Range Drop Drop Windage Windage Velocity Mach Energy Time Lead Lead
(yd) (in) (MOA) (in) (MOA) (ft/s) (none) (ft•lbs) (s) (in) (MOA)
0 -1.5 *** 0.0 *** 2556.1 2.268 1784.2 0.000 0.0 ***
100 2.3 2.2 0.8 0.7 2376.1 2.108 1541.7 0.122 21.4 20.5
200 -0.0 -0.0 3.2 1.5 2203.2 1.955 1325.6 0.253 44.5 21.2
300 -9.5 -3.0 7.5 2.4 2037.7 1.808 1133.8 0.394 69.4 22.1
400 -27.4 -6.5 13.8 3.3 1879.8 1.668 964.9 0.548 96.4 23.0
500 -55.2 -10.5 22.4 4.3 1730.2 1.535 817.5 0.714 125.7 24.0
600 -94.6 -15.1 33.6 5.3 1590.2 1.411 690.5 0.895 157.5 25.1
700 -147.7 -20.2 47.6 6.5 1461.1 1.296 583.0 1.092 192.2 26.2
800 -217.2 -25.9 64.6 7.7 1344.6 1.193 493.7 1.306 229.9 27.4

Might want to run them again, something is off with your data. I just checked my numbers and the Grendel wins in every category at 800 yards.

Post up your data. Mine is in the charts above using the JBM software and Bryan Litz calculated BCs.
I've run several comparisons and it looks to me like the 223 will beat the Grendel using the TMK. IF we could use the Lapua and get more velocity the Grendel gets closer but then we could use the .224 Berger 80 and gain with the 223. If the ballistics are better with less recoil, cheaper brass, cheaper bullets and overall load cost I'll stick with the 223. I just need to get to a longer range and test in the field.

I will once I can get to a computer.

We're at the range shooting now and buddy Jeff changed the velocity to reflect his 22" varmint barrel. I changed it back to what we are getting with the best accuracy load out of my 20" Krieger and CFE. Edited the chart above, it's closer but the 223 with TMKs still beats the 6.5 with the Amax.
For the last 4 or 5 years all I see on forums and gun rags is Grendel Grendel grendel and now that we are testing them side by side the 6.5 doesn't have as much of an advantage as we were lead to believe. When we weigh out the mag issues, bolts, cost of reloading and performance we are both thinking it isn't worth swapping over to the 6.5.

I didn't realize you were runnning those numbers with the TMK. Yeah, they are close. The .223 shoots a little flatter but windage seems to be pretty even at 800. I still think a Grendel with a 22" barrel being pushed as hard as that TMK would win (as in windage and impact velocity). Drop is a constant and is easily compensated for, I put much more thought into wing drift when looking at long range ballistics. Either way, I'll take whatever bucks the wind best.

I prefer to reuse my brass.

Wareagle 700 is right, your data is not right. I see 2 things that skew it.
First, although you said you changed the 223 data from a muzzle velocity of 2850 from your buddy's rifle to 2750 your data still shows 2857. Evan 2750 may be pushing it if your running a short throat.
Second the 123 gr. SST and the 123 gr. A-MAX has a BC of .510 not .462 as you stated in your original post.
Plug the correct data in and you will find the 6.5 still has the advantage and that why the guys that are in the know are saying Grendel Grendel Grendel.
Just a suggestion, accually do some shooting before you post your opinion relying on computer modeling which may not be right.
Doc

I understand looking at charts and such. Gives a reference point.

All BC are not the same either, but Litz has evened that out a bit.

I still trust only fired data and my personal fired data that summer said the 6.5 was better than the 223 with 90 jlks single load, driven around 2700ish FPS.... or maybe close to 2750 I don't recall anymore.

When you shoot enough, you realize what the impacts on paper in wind shifts tell you enough.

More so than any computer program actually.

That said, it always boils down to what your needs actually are and how much you want to invest in something.

It could easily go that the 223 suffices for one persons needs but not anothers.

Regarding the 75 Amax at mag length:

I tried it years ago with compressed loads of Varget (2.6 inches) and couldn't get it to shoot. So I shot 77 MK and was happy, or 80 MK single loaded for 600.

Awhile ago I read where rost495 said he'd gotten the Amax to shoot, so I tried again. Still no dice. So I Googled it and read that there is a mag (ASC) that lets you load to 2.314.

So I loaded some Amax to 2.312 to play it safe and went to the range to chrono different charges and see if this rifle liked that length.

To summarize, I got good results with 23.3 IMR8208, Hornady 5.56 brass, and Rem 7.5 in a Wylde chamber. 18 inch barrel gave me 2688, 2682, 2672, 2677, and 2650. So I loaded ten more and went back out. The load works in my gun even though it is still jumping a long ways.

So I ordered an ASC 10 round steel mag and two 20 round mags. The 10 doesn't drop out by itself, but the 20s do.

Anyway, something to consider. At my altitude I should be supersonic to 1K, but I haven't had a chance to yet.

didn't know anyone was making those again...

Will have to google.

BTW, going way back... short throated chamber, you could shoot 75jlks out of a cut out mag...

I don't recall, but they were pretty decent BC back then....

2,850 fps is a ridiculous velocity for the 77MK and even more ridiculous for the 77TMK.

Shoot that one all you please, I'll keep my face away from it.

Hard to say with new powders, barrels, bullet coatings and so on.

Though I've never shot a TMK.

I know years ago trying to get over about ?????? 2700ish out of a 77 SMK and 20 inch tubes was tough to get to safely.

He also presumes he can get that specific bullet to shoot well at that velocity. So far, I haven't seen any reports that would support that supposition.

I have yet to see anyone get good, consistent accuracy from the 77 TMK out on an AR.

What Iv'e heard has been the same, SMK stil more accurate by far than TMK.

Jeff, I'll bet your old 75 AMAX loads were better. (But still no Grendel killer)

nope. No grendel killer.

There always has been a differnece at times, IMHO, in what a book, ballistic program, BC, or chrono says and what you see in real life shooting real distances....

Fooled around some with a 1 in 9" .223. The 77 TMK was around MOA or so. The Berger 77 OTM did much better, and is a bit shorter bullet. I'm going to try it in a 1 in 7" Mk12

I bought three of the ASC mags, which allow an OAL up to about 2.31". Will try some 75gr Amax and other bullets, to see how they shoot.

They are shooting good for me in my BCM. Burned up 1k and got another 1k loaded. Using max load of TAC and a CCI BR primer.

What do you consider good?

You can do it safely today with CFE 223, I run 25.6 gr in my 18 1/2 inch Wylde chambered AR, am getting 2710, Hornady lists 26.5 as max with their 75 gr A max. I am also getting 2685 with 24.5 gr RL 15 with the 77 gr Nosler Custom competiton bullet.

Which ASC mag to order? To give you max length?

http://gunmagwarehouse.com/brands/asc

And how many shots.

The stainless mags:

http://www.ammosc.com/223-stainless-steel-20-rd-magazine/

ASC Stainless Steel magazines are an improvement on a classic, with the highest levels of durability and increased longevity, simply the best in the industry! Our magazines are manufactured 100% start to finish in the USA using .020 gauge 410 Stainless Steel Alloy, heat treated for superior strength and lasting endurance. Our magazines are chemically treated for corrosion resistance [ref QQ-P-35] and coated with our proprietary finish, Marlube which is a wear-in not wear-off coating that burnishes into the surface providing self-lubricating properties. The interior dimensions of OAL 2.316” ± .002 are perfect for reloads.

That's the one I ordered, thanks.

Tried a little experiment I read about, cut a slot front of
plastic 20 round mag, and got 75 GR A Max to fit and feed in my Bushmaster at 2.48" OAL.

hmm.. wonder how many years ago they started cutting fronts out of mags.

LOL

The true tested BC of the Amax and SST is not 510. That is Hornadys published BC but it has been proven wrong. We are shooting the loads I said and getting the velocities I said shooting 3 different Grendels and 4 5.56s side by side. .020" freebore doesn't make any difference in pressure because the bullets aren't stuffed into the lands.
My Iphone with AB program died so we started using an I pad and JBMs program online. The stupid thing works off their sever and changes the numbers as it finishes loading. At 300 yds the 77TMK is flatter than the 123, we can see that. We are working up loads at 300 to make sure we have the fastest accurate loads before we travel 2 hrs to the closest 1000yd range. Jeff and Bill were back out there today but i haven't heard anything. None of us plan to shoot more than 600 with these rifles, all of us have other rifles better suited for 600.
On another note have any of you tried the Beger 80gr Fullbore bullets in an AR loaded to mag length(2.28)?

Glad to see you are getting the velocity we are. The Wylde chamber doesn't shoot the TMKs as tight as we want them but the shorter throat works well when we load them out to 2.28 in metal mags. For accuracy work we stopped using mapul mags a few years ago.

10-shot groups under 2 moa. Not bolt gun accuracy by any means, but the same rifle shoots 53gr V-Max 1 moa or better with the same powder and primer.

Tag

Says about the bullet what I've heard...

If you shoot the TMK in a Wylde or 556 chamber loaded to 2.26 to fit in magpul mags the accuracy is not there. If they are loaded out to 2.3 and used in a Wylde the accuracy can be good or if they are loaded to 2.28 and used in a chamber with a freebore of around .040 instead of .061 they will shoot. We always look for 1/2MOA but sometimes settle on 5/8 or 3/4.

Shot some groups earlier today using 26 gr cfe 223 and the 69 gr tmk, pathetic, best group was about five inches, don't know why but cfe 223 and the tmk's don't work well, had good luck with AA2460, A2230 and exterminator.

I checked out the ASC site and saw that they make OEM mags for several manufacturers. Got me thinking...I have several different brand mags, plastic, steel and aluminum.
Got out the calipers and did some checking on the OAL possible with each.

Pmag plastic - 2.266"
Wilson Thermold plastic - 2.274"
Bushmaster Stainless - 2.313"
AR Stoner Stainless - 2.310"
Colt Aluminum - 2.264"

So, I think I will load up some 2.3" OAL loads and give em a try.
Always thought I was limited to 2.26"

Well my 2.48" OAL shot and functioned in 2 AR style rifles my 1-9 twist 20 " Bushmaster did not like the 75 gr about 4.5" groups.
The Ruger 556 16" 1-8 twist grouped under 2". Both fired with no fail to feed.

Yeah, 9 is too slow for 75s as a general rule.

The standard for function with the old AL mags we used for years, was always 2.250. There is no reason that others can be built a bit differently and as you found, you might be able to extend a hair... would be evident if you stuck a 2.250 round in one of the longer mags by looking at it, that it can take a bit more.

As long as there is a bit of free play you are fine.

The other thing to remember, most bullet seaters seat off the ogive, and bullet OAL varies a hair especially wiht OTM type bullets, so take that into consideration when setting up the seating die.