6.5x55 Ackley powder choice

J

jcl

Guest
Your help please. I am looking for guidance on powder choice and loads for a 6.5x55 Ackley rilfle that I have just had built. For info it has a Savage benchrest action (right bolt, left port) with a 30 inch 1 in 8 twist, heavy profile Broughton 5c barrel, a McRee benchrest stock and a Sightron SIII 8-32 mounted in Farrell rings and 20MOA base.

I have some 139 Scenars and 140 Berger VLDs to try in yet to be fire-formed Lapua brass and will be using it out to 1200 yards. I have read that the sweet spot for a 139 Scenar is around 2900 - 3000 fps which I am hoping is enough to keep it supersonic at 1200 yards.

I am fully prepared to do some load development but I'm looking to narrow down the myriad of choices using advice such as whether Vit 1XX powder is more suitable than Vit 5XX etc. My apologies if this has been asked before or if it is on the wrong forum.

All thoughts and suggestions will be greatfully received.
John.
 
I believe it was Steve Shelp, who also shoots a 6.5x55 Ackley, who did some case volume testing. Depending on the make of the brass, he found that the capacity of the 6.5x55 Swede and the 6.5/284 would swap. One would have more volume, then the other. That would mean that most of the loads for the 6.5/284 would be good candidates for the 6.5x55 ACKLEY. As always, start safe.

Steve also found that the case diameter at the head was different with Lapua, Norma, and RWS brass. As I remember, Lapua had the greatest diameter, then Norma, then RWS.

Maybe he'll chime in here.
 
Charles E said:
he found that the capacity of the 6.5x55 Swede and the 6.5/284 would swap.
Click to expand...

Given the lack of load info for the Swede Ackley this could be very useful, starting low of course and checking for pressure signs. Another method that has been suggested is to start near the top of the normal 6.5x55 load info and slowly go up. Any thoughts please?
 
6,5x55 AI

If one starts by loading a AI chambered rifle with near max load for the regular chamber one can assume he is 5-10% under the max load for the improved case (depending on what case we are talking about). Other methods can and will work but this one is a safe bet.

The punchline is, if in doubt start sufficiently low to be on the safe side.
 
jcl,
Hi, my friends have given you good advice so far. Dave Tooley built my first 65.x55AI in 2001. Since then he has chambered 5 additional barrels for me in that chambering. Both Charles and Dave have shot my rifles in competition also so they are pretty familiar with my equipment.
The water volume testing that I did back in 2001 showed that a 6.5x55AI Lapua case held 62.8gr of H2O, RWS held 60.6gr of H2O, and Norma held 62.6gr of H2O. At the time I had another shooter measure some of his 65.x284 Win brass that wasn't improved and he got a 62.5gr of H2O capacity. But his 6.5 Super (6.5x284 improved) held I think 68.? gr of H2O. Going on memory there so don't quote me.

Here are some of the powders that I have tried and my thoughts on how well they responded accuracy-wise:

all data below used Fed210 primers and 140gr bullets seated into the lands.


IMR4831 - up to 47gr. pressure signs were ok but didn't show much promise so never persued this powder any further.

IMR7828 - up to 50gr pressure was fine. Have more room to go up. Showed good accuracy and numbers on the chrono were very good. Would be worth a second look.

R25 - up to 54.5gr pressure was ok, accuracy was ok velocity was 3080. Never persued this any further.

H1000 - up to 54gr. This had decent pressure. Probably has a little more room to go up but accuracy was showing a lot of promise right in the 53.5gr region so I never went higher. velocity was 2930fps. I went back to this load more than once and would probably be my second choice of powder for this chambering with 140gr bullets.

H4350 - up to 48gr pressure was getting up there but still had more room to go if needed in case of hot weather. But the accuracy jsut wasn't there for me even though several of the 6.5x284 shooters said this powder worked great in their rifles. I jsut never got it to shoot very well. But more than one 6.5x284 shooter has won with this combo also. Just an FYI.

H4831 - up to 51.5gr velocity is right around 3000fps and this would be considered a max load for me without drastically shortening your case life.

50.5gr of H4831 after many years and barrels is my go to load for 140gr class bullets. this should give you right around 2925fps avg MV and adjust your seating depth and neck tension and tweek your load from here and I think you will be surprised. It's always worked for me.

Also as for the case head diameter yes RWS cases measured the smallest for me. My chamber measures .4785 (Dave keep me honest here!!) and RWS cases measure .4765/.4766" right out of the box. Lapua and Norma measured high .477?" out of the box. RWS has given me the longest case life but you can't get htem any longer. Lapua was very good for case life and Norma you have to watch the primer pockets. But I think I now have 15 or so loading on my Norma brass and they just barely hold a primer but they shoot and measure as well as the RWS and Lapua.

FYI: I know a lot of people think Lapua brass is the greatest stuff since sliced bread... but I've seen more than 1 batch of really bad 6.5x55 Lapua brass. And when I mean bad I'm talking .007/.008" out of round on the case wall just above the case head. The burn pattern on the necks are very uneven when these case were fired and the banana shape was real obvious when rolling the cases across the table before any sizing. But when the Lapua stuff is good... its a good stuff and tough.


good luck and always remember to work up when trying new loads and be careful. Let me know how your rifle shoots and where you end up as far as powder and load selection. Just surious if you end up with roughly the same results I get or if your discover some new powder also. Never tried any of the VV160, 165, or 560. But they have to be right there in the ballpark also.

Steve
 
Steve, all,
your replies have given me the info I need to make a safe start with a powder/case/head combination that will save me so much time and effort, I am very grateful.

Steve, in his reply Dave mentioned H4931SC, are you are using this or the non SC version? Can I substitute one for the other?

Thanks again to you all.
John.
 
John,
I have used both long and short cut versions of H4831 and ended up right back around 50.5gr for both when it was all said and done. The chrono never showed any difference worth talking about either.

have fun with your new toy!!

Steve
 
Steve Shelp said:
John,
I have used both long and short cut versions of H4831 and ended up right back around 50.5gr for both when it was all said and done. The chrono never showed any difference worth talking about either.

have fun with your new toy!!

Steve
Click to expand...

That info makes the choice easy Steve......whatever my dealer has in stock will be fine.

Thanks again to all for your responses, I will keep you posted how things progress.
John.
 
Boyd Allen said:
Steve,
How do you think barrel life for the 6.5 x 55 AE compares with the 6.5 x .284?
Click to expand...

Boyd,
Sorry for the delay... was out deer hunting. I keep track of my throat wear of my barrel from brand new until they are removed. Even though the 6.5x55 AI uses apprx 2-2.5gr less powder to generate the same velocity as a 6.5x284 you would think there would be a noticable difference in throat erosion.
But for all practical purposes you are still removing a barrel around the 1500rd mark and getting a new one for the next season because you know you can't make it through the whole next season. And when is a barrel truely "shot-out" also? My definition may be different than yours. But I've been able to get at least an honest 1500rds of competitive shooting out of my 6.5x55 AI barrels. That inlcudes LG barrels shooting 5 shot record strings and HG barrels shooting 10 shot records string with a few F-class matches thrown in there also on the LG barrels.
So the end result is there is no definitive difference in my book. The rule of thumb of 1500rds for a BR barrel for just about all center-fire rounds still holds true.

Hope this answered your question. If you want exact amount of throat erosion that I've experienced, I posted it here one time about a year or so ago. It should be in the archives. If not let me know and I'll dig out my data for you.

John,
Good luck and I would definitely be interested in your results when you settle into a good load for comparison purposes.

Steve
 
Steve, I've got a 30", 1:8.5tw 6.5x55AI bbl. for my BAT 3LL that's giving results very close to yours with H4831. The lot I'm currently shooting was old stuff packaged in a plastic bag and then boxed in a Hodgdon box, just like a lot of the old H322 was. The receipt was dated 1978, so I'm hoping it's not that different from my supply of current production 4831.

I shot a std. 6.5x55 in LR prone HP matches a few years ago, and had excellent results with N160, shooting either Lapua 139s or S142MKs. Suspect N165 may have a slight edge with the AI version, but haven't shot enough of it yet to have anything concrete to share.

Ditto your remarks on some lots of Lapua 6.5x55 - I'd bought several boxes from a retailer who specializes in target shooting equipment when they ran a special ($25/100) a few years ago, and really wan't all that happy with the runout at the neck. I purchased 200pcs. of RWS when I read here that it was no longer going to be imported. I can hear some guys hooting, but I gotta tell you, plain old bagged WW 6.5x55 has shot very well for me in this rifle, and neck runout with it has been very good.

I don't expect the AI bbl. to last forever, but since I shoot a much slower paced game than LR BR, it may go a little longer than yours have.

Thanks for sharing your experiences with the AI.
 
You must log in or register to reply here.
Back
Top