Thanks for that - sounds like it's worth a go if you're getting that from a shorter barrel. I've had a little read up online and Benchmark 8208/IMR 8208 XBR is also supposed to be very temp stable which is always good.
Thanks for that - sounds like it's worth a go if you're getting that from a shorter barrel. I've had a little read up online and Benchmark 8208/IMR 8208 XBR is also supposed to be very temp stable which is always good.
Greetings All,
What I failed to include in my post yesterday was that my son was getting 3,800 fps from 8208 with the 55 grain projectile in his 26 inch barrel and a max load from Hodgdons data. This is much in line with Tech,s results above. For the record Benchmark 8208 and IMR 8208 XBR are the same powder made in Australia. IMR 8208 XBR was introduced first by Hodgdons for marketing reasons as has happened in the past with their ADI sourced powders.
Regards Grandpamac.
Thanks for that @grandpamac - that is pretty encouraging. I noticed just now that Hogdon describe their Superformance as suitable for 22-250. Has anyone ever tried that? I believe Hornady have a 4000 fps factory load for the 22-250 but not sure if that's using Superformance.
Good info thks all. I've been trying loads for a Thompson Dimension. Not after super accuracy nor super speed. I've tried 55gn Hdy SP and the bulk 223 pill Rusa sells, 55gn FP. With Benchmark 2 in the 22-250 I'm getting 34500 fps average and poor groups at 50m but adequate for hunting body shots on goats at 150. A shade under max load. Same pills out of a 222 at 2840fps using an old can of ICI Nobel Rifle 2 group very well at 50m, reasonably good with Benchmark 2. Need to try some other combos. Will look to drop back a notch or two on the 22-250 first. See what that does. Cheers.
Good luck with it. BTW we haven't mentioned seating depth but in my case the lands are a long way off so I'm just seating pretty much to the book OAL of 2.350", which gives me plenty in the case neck. Seems fine so far.
WillB, some time ago I ended up with a bottle of Superformance with the intention of using it in the 22-250 but found no load data available for projectiles less than 60 grains in weight. I emailed Hodgdon and they replied saying they didn't recommend its use with the 55 grain or lighter projectiles.
For seating the Sierra 55 gr SBT two of my 22-250s OAL are set at 62.7mm (2.47") and one at 61.7mm (2.43") which puts the projectile .020" off the lands. I have never fully followed the theory that we need one calibre of bullet in the case as some cases such as the 223, 260 and 308 don't even have one calibre of case neck length.
Cheers for that. I'm going to try 60 gr partitions but they might not stabilise with the 14 twist. But I've picked up a bottle of 8208 XBR so I guess I'll see. Hopefully it'll work well either with the partitions or at least with the 55 SBTs. Should be interesting if nothing else. I also got a .224 bushing for my seating depth kit and with the partitions I can get right on the lands and still have a full calibre in the neck, so best of both worlds. I'm going to start at .030 or maybe like you .020 and see how we go. Good times!
Nosler recommend a minimum of 1:12" twist for their 60 grain Partition but 1:14" may work. If it is for deer I have found the Norma 55 grain bonded Oryx work well. They are also incredibly accurate in my 223s and 22-250s. Most times I have found that Sierra projectiles shoot well at .020 other than the 130 grain 6.5mm Gamechangers. When I altered the depth from .020 to .030 my groups halved in size. As you know there are no hard and fast guarantees with hand loading! Have fun!
Thanks that's really good info there. I had forgotten about the Oryxs, that's another option I'd like to try at some point. Can't find any sample packs of those though. Might just start with some factory loads as an indication.
Hi guys just to say thanks very much for all the input on this.
I tried the 8208 XBR yesterday, and the three different loads all shot under MOA with the Sierra 55 SBTs #1365. Best group was .46 and that was a gusty day here in windy Wellington. That group was doing 3550 in round figures so that's very much where I would like to be. Reckon I have a good load here and with a bit more experimentation and a still day it would probably shoot even better. So thanks for the suggestions on that powder - a step up. (Although by going slightly over max I got similar speed and group out of 2206H. But better not to be over max)
The 60 gr partitions were a dead loss - clearly not stabilising with 3-4 inch groups, so I won't persevere with them. I figure that the shorter barrel, 14 twist and relatively modest speeds of this rifle mean it isn't going to stabilise anything heavier than 55 gr. If you're going to do that with a 14 twist you probably need a longer barrel to get the velocity up as that would also increase the rpm. Does that sound plausible?
So it looks like the 55 SBT is the go, although I will be testing some Norma 55 Oryxes (and a big shout out to @Tech who had a few left over for me to try) I'll let you know how those go. I am thinking that they might be better on heavier animals.
Anyway, thanks again guys.
Will
I use the same projectiles as you but use w760 ball powder , 39g .
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Another powder that may be worth looking at is the new Winchester StaBALL 6.5. It is meant to be temp stable and US shooters are reporting high velocities. As far as I know it hasn't reached our shores yet.
Just to report back on progress. I found the IMR 8208 XBR excellent with the Sierra SBT 55 gr Game Kings. I get 3590 fps (and remember this is a short barrel for a 22-250) and groups of around .45 MOA. So that’s good. I’ve tried quite a few different seating depths so I’ll probably settle for that. The Norma 55 gr Oryxes unfortunately didn’t shoot at all in this rifle - so the only projectile I have tried which works is the SBT. There is still the 50 gr TSX or TTSX to try. But I’ve heard a few reports that the Barnes projectiles cause accuracy problems if you alternate standard jacketed projectiles in the same barrel. Has anyone encountered this? How much of an issue is it, if at all?
PS I shot a gong at 100 (offhand practice) and the AR500 was cratered. This is a gong which is impervious to 7mm RM, .308, 3006, 7 SAUM, you name it. But it looked like the projectile turned into plasma when it hit - the metal was actually melted into a little round crater. Incredible.
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