Official Grendel SBR/Pistol Velocity Thread

[LRRPF52]

We've gained a lot of data on 16-28" Grendel muzzle velocities commonly-encountered by the horde over the years.

I'd like to start a dedicated thread where we can reference recorded velocities of the shorter barrel speeds.

I'll kick it off with the format and my personal experience so far with my Faxon Group Buy 12" 5REE barrel. Let's try to keep it populated with mv data rather than discussions, so that it will be easy to reference without having to sift through posts other than data.

I know there are a bunch of you out there with 10.5"-14.5" data that many would love to see to get an idea of what to expect. I'll do the next post showing hand load format, which I plan to do next with my 12".

12" Faxon 1/8 5REE barrel

90gr TNT Federal AE 91˚F

2670 fps (5-shot avg @ 15ft ) MV= 2722fps

Suppressed (TBAC Ultra 5)

2683 fps (9 shot avg @15ft) MV= 2735fps


120gr OTM Federal AE 91˚F

Suppressed

2384 fps (11 shot avg @15ft) MV= 2418fps

[LRRPF52]

12" 6.5 Grendel, Faxon Group Buy barrel, 5REE

Hornady case, once fired
Rem 7 1/2" primer
CFE223
95gr Lehigh Controlled Chaos
2.255" COL

[Bigs28]

12" faxon group buy

I shot 123g SMK, CCI 450, COAL 2.265, XBR 8208
26.0 Average 2081.5 FPS
26.3 Average 2099 FPS
26.6 Did not chrono
26.9 Average 2168 FPS
27.2 Average 2205 FPS
27.5 Average 2226 FPS
27.8 Average 2249 FPS
28.1 Average 2273 FPS
No pressure signs noted. Primers looked perfect. Did not see a spike in velocities. I did not measure groups. This was mostly brake in, zeroing, and tuning the bleed off gas block.

110g Controlled Chaos, CCI 450, 2.230 COAL, CFE223
30.1 Average 2240 FPS
30.4 Average 2271 FPS
30.7 Average 2283 FPS
31.0 Average 2307 FPS
31.3 Average 2333 FPS
31.6 Average 2337 FPS
31.9 Average 2364 FPS
32.2 Average 2390 FPS
32.5 Average 2411 fps
32.8 Average 2441 FPS

110g Controlled Chaos, 8208, CCI 450, COAL 2.240

28.0 no data
28.3 no data
28.6 no data
28.9 Average FPS 2323
29.2 Average FPS 2340
29.5 Average FPS 2363
29.8 Average FPS 2376
30.0 Average FPS 2411

[rosey]

10.5" x-caliber barrel 5 shot groups...

Hornady ELD-Black 123 factory -2210fps average ~1.5MOA
Wolf steel 100 - 2330fps average ~2.5MOA
Federal gold metal berger 130 - 2090fps average ~2MOA
Speer 90 TNT with ramshot TAC (33.4 grains) - 2555fps ~1.5MOA
130 rdf tried 8208 varget ar-comp - all maxed out just over 2100fps tried lots of loads and seating depths, best case was 1.3MOA, most groups 2MOA+
123 eld-m 28 grains 8208 - 2190fps average ~1.5MOA

Not unhappy with the hornady black factory ammo, still have some work to do to find something better. Spent most of the time so far trying to make the 130rdf work but giving up as it just doesn't seem to want to work. Going to try something else as soon as I can find a deal on some other 123-130 grain match bullets.

ETA - tried some norma 130s with ar-comp and cfe223, got marginally better accuracy over the 130 rdf but still haven't found that magic sub-moa load that I know this pistol is capable of. Velocity got up to 2146fps on ar-comp and 2251fps on cfe223.

[grayfox]

I don't have a lot of data yet, but here are some for my 12.7 Faxon GB, 5Ree.

Factory Federal 90 gr TNT - 2628, sd-20.6
90 TNT w/ AA2200, 29.2 gr - 2539, sd-9
100 Eldm, handload, CFE223, 33.2 gr - 2452, sd-9
Only a few 110 CChaos w/ CFE at 29.8, 2455 but need to shoot some more of these.

Hdy Black 123, 2217, sd-11
Hdy 123sst, 2263, sd-10
123sst w/ CFE 30.8, 2289, sd-12.9

[Bigs28]

Only a few 110 CChaos w/ CFE at 29.8, 2455 but need to shoot some more of these.

At 32.8g of cfe i was averaging lower velocity than you. Does 0.7" of barrel length add this much velocity?

[grayfox]

CFE is "kind of" a slow powder, one whose pressure curve is longer than other powders...
Don't know, could be something else going on; at some point I need to get back to this load and shoot some more.
I consider my CChaos data right now to be tentative.
First thing I need to do is polish the chamber a bit more, with '52s chamber brushes (which came in couple of days ago!), then shoot some more rounds.

[Bearcatrp]

Make this a sticky thread.

[Bearcatrp]

Here is what I have so far. I use a labradar.
Before I had the upper sent in:
4-23-18, St. Cloud Mn, 68 degrees

2314.26 avg 3 shots, Federal Fusion commercial 120 grain
2230.14 avg 4 shots, 8208, 27.3 gr, Hornady 123 SST, CCI primers
2254.38 avg 5 shots, 8208, 27.6 gr, Hornady 123 SST
2267.29 avg 5 shots, 8208, 27.9 gr, Hornady 123 SST
2292.07 avg 4 shots, 8208, 28.2 gr, Hornady 123 SST
2323.30 avg 5 shots, 8208, 28.5 gr, Hornady 123 SST
Bad grouping all shots

4-26-18, St. Cloud mn, 55 degrees
2212.08 avg 5 shots, 8208, 27.3 gr, Hornady 123 ELD-M CCI primers
2248.45 avg 5 shots, 8208, 27.6 gr, Hornady 123 ELD-M
2269.86 avg 5 shots, 8208, 27.9 gr, Hornady 123 ELD-M
2292.36 avg 3 shots, 8208, 28.2 gr, Hornady 123 ELD-M
2312.85 avg 5 shots, 8208, 28.5 gr, Hornady 123 ELD-M
Bad grouping all shots. Sent upper back for inspection while I had my back surgery.

7-16-18, St. Cloud Mn, 80 degrees
2270.00 avg 8 shots, Alexander Arms Nosler 120 gr BT
2101.32 avg 5 shots, 8208, 26.6 gr, Nosler 120 Spitzer
2132.88 avg 5 shots, 8208, 26.9 gr, Nosler 120 Spitzer
2172.36 avg 5 shots, 8208, 27.2 gr, Nosler 120 Spitzer
2205.63 avg 5 shots, 8208, 27.5 gr, Nosler 120 Spitzer

Grouped fairly well. Sulzar firearms took it apart to inspect. Said nothing wrong. Still think they did something. The SST and ELD-M shot horrible previously. Just did a batch of both to try again, hopefully next week. Will let you know how it goes. I did order and installed a 3 lb timney trigger after my last range trip. Went back out to the range with the AA 120 gr nosler for a function test. Grouped allot better.

[LRRPF52]

Bigs28:

How are you measuring MV?

[Bigs28]

Caldwell chrono about 3 feet in front of my muzzle.

Does something look off?

[LRRPF52]

Caldwell chrono about 3 feet in front of my muzzle.

Does something look off?

No, just was wondering if you needed to back-calculate actual mv. A word on chronographs:

If you place an optical chronograph close to the muzzle, your readings can be skewed by muzzle blast moving the unit, depending on whether or not the face of the chronograph base is within the blast wave propagation of the muzzle.

I've seen some video of guys testing a 6.8 that way, and you could see the chronograph rocking back and forth with each shot.

[A5BLASTER]

Not sure what Caldwell unit you have but the instructions for mine say not to place it closer then 15 feet from face of muzzle.

[Bigs28]

Instructions......pfffft. the biggest problem with moving 15 feet out is that my chrono is now in direct sunlight which messes it up.

[A5BLASTER]

Instructions......pfffft. the biggest problem with moving 15 feet out is that my chrono is now in direct sunlight which messes it up.

Yea I don't such problems. I tend to work around them or eliminate them.

Anyway wasn't trying to sidetrack merely stating some Caldwell info.

Will soon be doing up a 12 inch grendel of my own.