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Velocity and powder conundrum - Printable Version +- 6.5 Grendel Forum (https://65grendel.com) +-- Forum: 6.5 GRENDEL DISCUSSION FORUMS (https://65grendel.com/forumdisplay.php?fid=3) +--- Forum: 6.5 Grendel Ammunition & Reloading (https://65grendel.com/forumdisplay.php?fid=10) +--- Thread: Velocity and powder conundrum (/showthread.php?tid=24852) |
Velocity and powder conundrum - Modoc - 08-24-2022 trubulator Wrote:Always a good idea. I got no pressure signs, but I also know that can be deceiving with an AR. This was in a Howa 1500 Mini. I was loading middle of the charge window plus 10% of the window for practice ammo. This has worked very well before resulting in several MOA or smaller loads in various rifles, just this time the two data were significantly different. Nosler Max is 27.5gr and Hodgdon is 38.0gr 28.0gr Velocity and powder conundrum - sundowner - 08-24-2022 The brass is Starline and the Ogive is 1.169" and I never load above the manufactures Max load , either bullet or powder max . 28.7 has been hodgdon's for many years . Also thir listed PSI is 49,800 and 2508fps . Velocity and powder conundrum - sundowner - 08-24-2022 dexdog Wrote:Sundowner, not to be jerk, but Hornady Ten says that max load using 123 SST and H335 is 26.4gr with velocity of 2300fps. Also Quickload shows that 28.7gr of H335 pushing a 123gr SST has velocity of 2553, with pressure of 58,585psi. Your velocity agrees well with the Quickload numbers. I am well aware that QL is only an estimation, but it seems that you have really hot load at 28.7gr. QL gives a velocity of 2365 fps sat the Hornady max load of 26.4,with pressure of 44,759psi using standard QL parameters for temp and elevation. I have used 25.5gr H335 and 123 SSTs with an 18 inch Grendel Hunter upper and have chrono'ed about 2250fps. I use the powder manufactures load info and that load that you are talking about has changed over the years and additions , it has gone down , their load is below the fps listed on their ammo box . Velocity and powder conundrum - VASCAR2 - 08-24-2022 Part of velocity discrepancies in listed sources is barrel length used for testing. Hornady has used 14.5, 18 barrels and possibly other lengths depending on the particular reference manual. Western/Ramshot/Accurate used 20 barrels where Speer, Sierra, Nosler and Hodgdon use 24 barrels for testing. Velocity and powder conundrum - NDSwede - 08-24-2022 Very good discussion, I've appreciated reading it. Here's a couple thoughts for future consideration. 1. Your current load doesn't really have enough velocity or energy to shoot 400 yards. You need about 2550 fps mv to have 1000 fpe at 400 yards. Also 1900+ fps is required on target to initiate expansion. 2. As has been stated Leverevolution gives the highest velocity of any powder I know. It is temp sensitive though. 3. Metal magazines like the AR Stoner allow you to load out to a COAL of 3.100". Velocity and powder conundrum - Harpoon1 - 08-24-2022 jasper2408 Wrote:Hodgdon shows 28.7gr for max load of H335 on their reloading data page. That's with a Sierra 123 gr bullet. So Hodgdon uses a 24 1/9 twist barrel and the Hornady data is out of 18 1/8 barrel. If you subtract 150 fps, for the differences in barrel length. Say around 25 fps per inch! Youre basically only 50 FPS apart for additional 2.3 grains of powder! Somethings off, somewhere! The only other thing I can see, the SST has cannelure and the Sierra doesnt. So one is crimped, should have a lot higher neck tension than the other that isnt! Edited: just checked the Sierra data and they show 28.2 grns/2490 fps as their max, with 123 BTHP and 24 1/8. Velocity and powder conundrum - trubulator - 08-24-2022 NDSwede Wrote:Very good discussion, I've appreciated reading it. Here's a couple thoughts for future consideration. So there is another question I have been wondering about. My usual MO as a hunter is to be a sneaky bugger and get right on top of my quarry for a close in shot. We do a muzzleloader hunt every fall and I take deer well within 100 yards. Last fall I shot a pronghorn within 75 yards by using the terrain and being extremely sneaky. So my experience of shooting game at 300+ yards is nil. I am trying to stack the deck in my favor for the first attempt, so I have deliberately chosen to work with SSTs, which Hornady says expand starting at 1600 FPS. When I plug my particulars into a ballistic calculator, I get 936 foot pounds and 1851 FPS at 400 yards. Maybe I am missing something, but I am assuming that being 250 FPS over minimum expansion velocity as disclosed by the manufacturer and darn close to 1000 ft pounds should drop a whitetail doe, no? Since I have no terminal experience, I would be interested in what others' have seen. Ideally, I will be a lot closer when (heh, if) I shoot. That said, I have hunted this property for years and much of it has very little cover for me to be sneaky in, so a long shot is a definite possibility based on past experience. I hope to be luck and make it a close shot, but I would rather be prepared to take the long shot if that is all that is offered. Velocity and powder conundrum - PA_Allen - 08-24-2022 Trubulator, Dont sweat it. If you fire a 123gr SST at 2400 fps and place your shot, you will cleanly kill any deer on that property. I shot that combo for years out of my 16 Grendel (123 SST, 2400 fps) and killed dozens of deer from 20 to 350+ yds. Go hunt with confidence and have fun. - PA Velocity and powder conundrum - trubulator - 08-24-2022 PA_Allen Wrote:Trubulator, Thanks. I am looking forward to the chase. If this combo works, I will use if for pronghorn next year when I expect to get another tag. I am planning to hunt bear in September with a 35 Rem. If it turns out that likely shots will be longer than 150 yards, I may switch to the Grendel. Velocity and powder conundrum - NDSwede - 08-24-2022 Heres a very interesting video on the subject of velocity required for expansion. His bullet should be hitting at about 1780 fps. As he shows there is no expansion at that velocity. My ballistic calculator shows your bullet should also hit at about 1780. Personally Id call your load a 300 yard gun. It should hit at 1925 fps and 1010 ft pounds of energy. https://youtu.be/XiEx_JQCfbg Velocity and powder conundrum - trubulator - 08-24-2022 NDSwede Wrote:Heres a very interesting video on the subject of velocity required for expansion. His bullet should be hitting at about 1780 fps. As he shows there is no expansion at that velocity. Hmmm, when I plug my particulars into a calculator I get 1915 FPS and 1002 FPS at 350 yards. Part of it is that I am correcting for elevation and atmospheric conditions, which probably gives me a bit more range (4350' elevation, low humidity, basically high plains/desert). At 400 yards I get 1851FPS and 936 FPE. I'd probably be happiest to keep this to 350 yards. Velocity and powder conundrum - VASCAR2 - 08-24-2022 Here are velocities I got for factory Hornady 123 grain SST at 70 degrees using a Magnettospeed chronograph with AR-15s. Just for reference a Friend used his 24 6.5 Grendel AR-15 to take a buck antelope at 500+ yards at 7200 ASL in Wyoming. My Friend was using a Max load of A-2520 with a 120 grain Nosler hunting Ballistic Tip. He had used this load to take numerous antelope, some with his 18 6.5 Grendel and some with his 24 AA 6.5 Grendel. 123 Grain SST Hornady 12 2277 (chrono by forum member with lab radar) 16" 2430 18" 2493 20" 2511 24" 2583 Just for comparison here is a hand load using 31.0 grains CFE 223 and 123 grain Nosler CC I chronographed on the same day. LeveRevolution will give very similar velocities to CFE223. I got basically the same velocities using 123 grain A-Max as Nosler CC. Hand Load 123 Grain Nosler CC, 31.0 grains CFE223, CCI 450 16" 2449 18" 2471 20" 2526 24" 2619 Velocity and powder conundrum - NDSwede - 08-24-2022 Wow, I reread my previous post regarding COAL. Max COAL is not 3.100. On my Ar Stoner mag its 2.310. That makes a lot more sense. ???? Velocity and powder conundrum - trubulator - 08-24-2022 I am seeing CFE 223 available. Is the temp sensitivity enough of an issue to really make me want to avoid it for a hunting load powder? Velocity and powder conundrum - NDSwede - 08-24-2022 Vascar2, I get very similar velocities using LeverEvolution as you do with CFE223. Ive got a 20 barrel Ar. Im getting 2557 fps from 31.4 grs of Lever. All the usual precautions, etc, etc. Velocity and powder conundrum - DIANEB - 08-25-2022 trubulator Wrote:I started loading Grendel this summer. I am working with factory starline brass and 123 grain SSTs fired out of a 20" BCA upper. I have been working with the powders I could get, namely TAC and H335. My goal is a 350 to 400 yard load for deer on a piece of land where there is little cover and shots might be quite long (could not get closer than 400 yards last year with a rifle that was good for 200). I have been loading to a couple thousandths over the Hornady book min of 2.245" and ran through a couple rounds of ladders to arrive at a couple of good loads. The best TAC load was 27.0 grains with ES of 21 and SD of 8 and average velocity of 2358. The best H335 load was 27.4 grains with ES of 30, SD of 14 and average velocity of 2401. I am running out of time to do load testing, so I decided that the H335 load would have to do and loaded up 3 boxes for the Fall. So at least for now, I am going to run with what I have.If you can find A2520 give 28.5 grains a try with 120 ELD and the 123 SST both shoot great out of my BCA 18" velocity should be about 2450 fps... Also 26.5 grains of Benchmark shoots great too... Velocity and powder conundrum - trubulator - 08-25-2022 DIANEB Wrote:If you can find A2520 give 28.5 grains a try with 120 ELD and the 123 SST both shoot great out of my BCA 18" velocity should be about 2450 fps... You'd figure two and a half or 3 years into the shortage things would be getting better. Maybe, but excruciatingly slowly. My bad luck to be chasing a new cartridge due to banged up shoulders. I will probably pick up a pound of CFE223 while it is around and keep an eye open for 2520. Some day 8208 might finally be available. I liked TAC pretty well, but it didn't have the necessary velocity. Maybe I will burn the rest of the pound up in target loads. Seems like it would also work in 223 or 35 Rem. Velocity and powder conundrum - DIANEB - 08-25-2022 trubulator Wrote:You'd figure two and a half or 3 years into the shortage things would be getting better. Maybe, but excruciatingly slowly. My bad luck to be chasing a new cartridge due to banged up shoulders. I will probably pick up a pound of CFE223 while it is around and keep an eye open for 2520. Some day 8208 might finally be available. You'd think things would be getting better by now but I still think the government has something to do with the shortage... Velocity and powder conundrum - trubulator - 08-25-2022 DIANEB Wrote:You'd think things would be getting better by now but I still think the government has something to do with the shortage... And CFE 223 is gone locally. I can fine 2520 online, but I don't want an 8 pounder. Guess I will be patient and watch for 8208 and 2520, with cfe 223 as a possibility. Is there published data for leverevolution, or is this wildcat stuff? Velocity and powder conundrum - NDSwede - 08-25-2022 Kind of wildcat. If you look at BFTs list of favorite loads you will see several loads. |