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7MM/06AI
Posted: Sat Apr 14, 2007 9:09 pm
by Matt P
Tony Z, JR & Dave G
What sort of powder charges of 2213sc and 2217 work in this caliber ??
Ran my new barrel in today and then shot 4 x 5 shot groups, 2 using 55gr of 2213 and with 168SMK and 162Amax total group went about 1" @ 300 for both projectiles, the other 2 groups were 51gr of 2209 with 168 & 162's, the groups went about 3" @ 300 all verticle. All loads where fireforming cases but it seems to have a preference for the slower powder.Have no idea of velocity, primers showing no signs of pressure so I suspect these are light loads.
Matt P
Re: 7MM/06AI
Posted: Sun Apr 15, 2007 8:31 am
by a.JR
Hi Matt, 1st i must say that the 2213SC is the worst powder we have ever dealt with , i won't even use it to fireform.. It has the capability of powder fouling so badly that it is impossibile to remove without a JB style abrasive .. It also won't repeat in the pressure as the weather changes .. It is a good powder if you want to loose matchs up here.. I think as i said before if you can get H4831 ,it's the ticket in that burning range or Re22..My brief run with 2217 wasn't great but TZ has had good results .. The yanks seem to get top accuracy with a case that is large enough in the first place to hold a healthy supply of the slow burning powders from the 4831 area on to the Re25 style ..This has been a failure for me , guess it's our hot ,hi humidity enviorment,but i don't know for sure..
Observations, 09 does not work at soft pressures,your case should need more gns as i see it to get the vertical out.
2217 according to a mate in the US will give you an increase in barrel life of at least 20% over 2209 at the same pressures.
if you have heavy residual powder left in the barrel after a 10 shot string then bin that powder,it is only going to cause you grief!!
Strange things happen after the case is fireformed sometimes,the results may not be the same ,retest..
Go with what works, regardless of what someone else says ..
Tony has had some good batchs of the Amax,i have not ,if you can repeat the 5 into the 1in @ 300 again i would buy up all of that batch available
JR..Jeff Rogers..................
Matt P wrote:Tony Z, JR & Dave G
What sort of powder charges of 2213sc and 2217 work in this caliber ??
Ran my new barrel in today and then shot 4 x 5 shot groups, 2 using 55gr of 2213 and with 168SMK and 162Amax total group went about 1" @ 300 for both projectiles, the other 2 groups were 51gr of 2209 with 168 & 162's, the groups went about 3" @ 300 all verticle. All loads where fireforming cases but it seems to have a preference for the slower powder.Have no idea of velocity, primers showing no signs of pressure so I suspect these are light loads.
Matt P
Posted: Mon Apr 16, 2007 9:47 am
by Tony Z
Matt, just this weekend i had my 280 AI out for a run with 2217. Initially i was ready to wrap it around a pole but after some investigation last night i found that my 505 scales were reading plus .2 to minus .3 grains when supposedly reading on the line. I never take my 1010 to the range and paid the price for it Saturday. Anyway, i can't quote accuracy because of the obvious scale inaccuracy, but speed with a start load was 56 grains of 2217, 168 SMK at 2800 fps neat. 60 grains was at a very light compressed charge giving a speed of 2980 fps. Of all the groups, which were quite poor with a lot of vertical at 200 yards, the 59.5 grain charge gave 2950 fps and the only group under the inch, but still vertical. Pressure even at 60 grains was still easy on the brass and extraction was OK and the case could be re-chambered without too tight a bolt close. Last week i shot this rifle at 1K with the 168 SMK and 51.75 grains of 2209 and it shot a 5.7 incher first up. 2209 at this loading and beyond (54 grains) are hard on the brass. Speed was only 2880 with an extreme spead of 13 fps when fired over a tacho during the match. With 09 the speed is down with the pressure up. Not a good combo. Re 22 at 57.5 grains or 58 grains of H4831 and the 175 SMK is hard on the brass aswell, but is good for accuracy and gives a touch over 2900 fps. Don't like the 175 when things get choppy and show a tendency to go a bit vertical. The 162 Amax with 60 grains of 2217 gives 3030 fps, good accuracy and is stable when things start to flick around. The 160 CDC with 58 grains of 4831 is also at 3030 fps with good accuracy, but drifts a long way compared to the other three pills, about a third as much again.
Tony Z.
7mm 06 AI
Posted: Mon Apr 16, 2007 10:00 am
by dg
Matt
In my old light gun (280 ackley) the best powder i found was 2214 ( about 63 grains with 168's) but unfortunately it has been discontinued for quite a while. I did try 2213 ( not the short cut) and soon gave up and went to 2217 which i have been using for 1000yd since 2003. depending on the batch, i have found that the 1in 10 tobler seems to do ok with loads in the 60 -61.5 grain region with 168's and the 162's with 61-62 grains.
i have recently tried 2225 with 175's in the 29" 1-9.5 tobler heavy gun (7mm 06 improved) which shot ok, but in my opinion there was insufficient ignition occurring, as evident by significant powder residue on case necks and in the barrel. last week in cooler weather ( about 25 degrees c) with 175's, 58 2217 gave approx 2720 fps, 59 2217 gave approx 2760 fps and 60 of 2217 gave just over 2800fps.
hope this maybe of some help
dave
7mm o6 AI
Posted: Mon Apr 16, 2007 2:07 pm
by dg
Matt
also meant to ask previously, what cases and primers are you using and how much reduction in length on fireforming occurred.
cheers again
dave
Posted: Wed Apr 18, 2007 9:47 pm
by Matt P
Hi Dave
Using Lapua 30-06 cases, they're not as good as some of their other cases but stil better than rem or win. I've been tempted to try the Nosler premium brass but haven't heard what it's like yet.
In 30-06 form they measure 2.485", when necked down to 280 they measure 2.491" and when fire formed they measure 2.466"- 2.476".
The chamber isn't a full length 280AI the reamer has been run in short to suit the 30-06 length rather than the 280 length which is longer ( about 0.090").
Matt
7mm 06 AI
Posted: Thu Apr 19, 2007 12:51 pm
by dg
matt
according to the new australian norma importer, norma is now also making formed 280ackley brass and some is destined for australia.
it would have been nice to know this about 6 months ago.
i may have been tempted to take the risk (hoping the present 280 brass is harder than the past batches) and go 280 ackley again with the heavy gun.
but too late now !!!
cheers
dave