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View Full Version : Sierra 70 gr HPBT Match Not A Good Choice?



beartooth91
05-28-2010, 01:42 PM
Hi every one,

I've been out of shooting and reloading for 25 years and have dived back in, purchasing two Savages - a 2006 Model 14 Classic in 7mm-08 thats been sitting on the closeout rack and a newer 11FHNS in .243 with the Accustock. For the .243, I've got some Sierra 70 gr HPBT Matchkings and I shot some initial groups yesterday with H380 (40.0 grains). I wasn't impressed with the results. I also found the throat in this rifle is long and I can't even get close to lands, so, I'm seating to 2.625" COAL. (In my 7mm-08, I seat to .020" back from the lands.) I loaded up some more with IMR-4064 and we'll see if it likes it any better. Has anyone been able to get this bullet to shoot? Are there some better choices in the 70-87 gr range?
Thanks,

Mark

Armed in Utah
05-28-2010, 04:07 PM
Try some longer/heavier bullets...

90 Nosler BT
87 V max

What ya planning on shooting at ? Don't give up hope

on the rifle with one bullet & powder selection..........

possum1
05-28-2010, 04:16 PM
Welcome to the forum beartooth91, I've used the Berger 70's with IMR 4350 and 4320 with good result's. the only draw back is they are a little expensive. Sometime's you can catch them on sale at Midway. Just got some Berger 68's in today I am going to try they are quite a bit less money. The 4064 should do better with the 70's.

pa_wdchuckhuntr
05-28-2010, 04:49 PM
I have a Shilen barreled 6.5x55 that likes a long jump (.120) with 140gr Bergers so getting near the lands with your .243 may not be terribly critical.

I'm a big fan of the 87gr V-max out of 6mm's for varmints. I've always got very good accuracy with them and they seem to have just the right amount of weight for woodchucks to get devestating terminal performance(big exit holes). I'm doing some terminal performance testing with 70gr Blitzkings with Reloader 17 right now but most of the time I don't get an exit hole even at a 3850fps MV. They're still DRT though.

rcinit
05-28-2010, 05:09 PM
I have a new Mod 12 VLP 243 cal. I've tried Hornady 58gr vmax, 75 gr vmax, 87gr vmax and sierra 85gr Hollow point boat's and 100gr spitzer boat tails @100 meters. While none of them have shot larger than a 1.7 group. The smallest and most consistent groups for me were obtained with the 87gr vmax bullet's. Most 3rd shot groups were in the .4 to .6 range. Measure from the center of the hole. Best 3 shot group was .24 from center hole to center hole. The worst was .8. Shot in light 5-7 mph winds temps around 90 using 36.1gr of IMR 4064 with federal cases, bullet set .005 off the lands. I'm sure with a better trigger man the shot groups would be even tighter. The largest shot groups were with sierra 100gr bullets. I was using them to break the barrel in and wasn't too concered with the shot group. After all they were shot in 25-35 mph gusty wind conditions at 100 meters.

beartooth91
06-01-2010, 09:32 PM
Ok...I was about to rush out and procure some IMR4350 or H414 in an effort to get these Sierra 70's to shoot. But, after looking through the manuals over the last two days; the data **suggests** the slower burning powders like 4350 or 414 favor the medium to heavy 6mm bullets. It may also **suggest**, though much less clear, that a medium slow powder may go well with the lighter bullets. So, I'm going to load some up with good 'ol IMR4064. Any other powder suggestions for this bullet?

desertdog
06-01-2010, 11:51 PM
i like imr 4350 and r-15 in the 243.

82boy
06-02-2010, 10:23 AM
The 70 SMK's have always shot lights out in all my 243's. You using the wrong powder, try something faster like benchmark. I had one 243 that would shoot 5 shoot 100 yard groups in the mid .2's all day long with benchmark, 70 SMK's, and a BR2 primer.

beartooth91
06-03-2010, 01:10 PM
Well, I thought a slightly faster powder like IMR-4064 would give me better results, but.....
I shot 5 3-shot groups, ending 1/2 grain below max.
The 1st was just a hair over an inch.
The next two were right at 1 inch.
The 4th was 15/16 of an inch.
And, the last was 1-3/4 inches - two close together with one flyer.
I'm gonna try another batch with H414.

MARK25-06
06-06-2010, 05:04 PM
using 87gr v-max, try 46.7gr h4831 shoots .500 in mine MARK25-06

possum1
06-06-2010, 06:49 PM
RL15 is looking good for me using the lighter bullet's.

DannoBoone
06-07-2010, 10:35 PM
My 12 VLP .243 barrel is just at the point of being broke in, and has
done its best with the the 70 SMK and 42.5gr RL17. It got only 3100fps,
but with .25" groups with no signs of excess pressure, so will increase
the number of grains next time out.

Dennis
06-08-2010, 02:01 AM
My VLP 243, 70gr Nossler Ballistic Tip's, .015 off the lands

The gun will also shoot 55gr NBT's, and 107 SMK's

The 55gr NBT's, 43.1gr Varget, go by the manual COAL, they are way off the lands but shoot 1/4 groups

http://i957.photobucket.com/albums/ae56/Dennis4437/243best70gr.jpg

http://i957.photobucket.com/albums/ae56/Dennis4437/243best107smk395IMR43502.jpg

beartooth91
06-08-2010, 11:00 AM
I put some cartridges together, yesterday, with the Sierra 70's and H414. We'll see how that shoots. I also bought some Nosler 80 gr BT's, which I'm more hopeful about. Looks like I can get these close to the lands and I bet the 1:9.25 twist will like these better.

MZ5
06-09-2010, 05:40 PM
I hope/bet the 760 (aka 414) will do you good. Only 70s I've shot through my 243 are Speer TNTs, but they perform exceptionally over W760/H414.

flatshooter
06-10-2010, 06:05 AM
What twist rate is the barrel?

beartooth91
06-11-2010, 08:31 PM
What twist rate is the barrel?


Its a 1:9.25" barrel twist rate. I need to be drug tested as I thought the .243 standard was 1:10".

beartooth91
06-30-2010, 08:24 PM
Well, I had about given up on the Sierra 70 HPBT MK. But, my very 1st group with 43.5 grns of H414 netted me a 5/8" group. Went back today and my 1st 3 shots with 44.0 grns of same netted me a 1-1/4" group???!! The next set of 3, at 44.5 grns, gave me a 7/16" group! Go figure.
It seems the rifle likes this powder/bullet combo. Not the best groups, but, it does appear its capable of shooting this bullet and these were all with new, FL-sized brass. I'll repeat these after running them through my Lee collet die.
One stupid question - I've been reading this book, "Precision Reloading and Shooting", by Sinclair. It suggests starting a range session with a couple of "fouler" rounds. What's the deal and could that be a possible reason why my 1st three shots gave me a bad group (I didn't shoot any foulers)?

possum1
06-30-2010, 10:39 PM
I alway's shoot fouler's when I'm shooting group's. To me it's kinda like doing a burn-out before going down the track when your drag racing. Getting the barrel "warmed up" .