Sierra 155gn MKBT

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Dreamcaster51
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Sierra 155gn MKBT

Post by Dreamcaster51 »

Hi guys, newbie here so be gentle :D
I could only afford a Howa for my new 308, 24" barrel, heavy barrel
with a 10 twist.
I am shooting Sierra 155 mk using 2206h powder, reason being I use this powder
in my 223, I am on the pension so I try to use one powder only. :lol:
I have tried 39.5 gn of 2206h behind the pill and get quite good
clover leaf groups BUT the group is 4 inches below where I aim. I realise
I could just alter the scope but it seems too light.
I am getting 2550 fps at this load but it seems slow to me.
I have tried 43gn with a reasonable group but O am asking if any one
that has the same set up is having sny luck. AsI said I am new to this
bench rest shooting and am loving it but I would like to get better
groups.
Any help would be appreciated, thanks.
johnk
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Re: Sierra 155gn MKBT

Post by johnk »

That 39 is a fairly soft load for 2206H with 155s. Have you checked out the ADI Web site?

http://www.adi-powders.com.au/handloade ... Winchester
scott/r
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Re: Sierra 155gn MKBT

Post by scott/r »

I'm running 45.0 of 2206h in a 32" barrel, so you have a fare way to go yet. 2550fps is quite a bit slow as well. You'll get blown around a lot and your elevations will be through the roof by time you get back to the longs.
If I were you, I'd start looking for a load at about 44.5 and work your way up from there. You should find another node around there.
Dreamcaster51
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Re: Sierra 155gn MKBT

Post by Dreamcaster51 »

Thanks for the comments, I thought it was a bit gentle, nice to shoot though :-)
My friend has a Ruger Tac type rifle with all the addons, his is 24" one in 10 twist as well and he is shooting 43gn of 2206h with the same pill and doing
quite well. I just thought I would check.
Thanks once again.
argh
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Re: Sierra 155gn MKBT

Post by argh »

I was shooting 155s in my factory howa barrel using 46.0gr of 2208 for atound 2820fps. I never got 2206H to group very well ??
Just note that the factory barrel has a very long throat so seating anywhere near tge lands means only having 2 to 3mm of projectile in the neck
Dreamcaster51
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Re: Sierra 155gn MKBT

Post by Dreamcaster51 »

Thankj Argh, found the same. Good friend of mine checked for me as I thought I was wrongbut very long throat. I now load around 2.200" for thr 155. I am going to try some 2308 with Ferderal match primers to see if I get any improvement. I also have some 168gn and Hornady 180gn to load as well.
Dreamcaster51
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Howa 1500 308 24" 10 twist

Post by Dreamcaster51 »

OK ended up sending my rifle back to the agent as they asked to have a look. To their credit they were very good about it. I got it back with a target showing two groups like mine BUT one group under .030" using Hornady 155gn Steel Match factory loads. The question I ask now has anyone got these little buggers in their ammo locker that could measure them for me. I am after the COAL and Ogive so I can have a try a duplicating them. Why not just go and buy some you ask? well here in the river land they are $85 per box and I ain't got those bucks. If any one can help with the info it would be great. thanks
MR.Sako
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Re: Sierra 155gn MKBT

Post by MR.Sako »

first of all your way under the minimum load for 06h which is 43 gr second of all try the 155gr hbc. i have a mate with a howa varmint in 308 that shoots hbc's incredibly well with a 15 thou jump.
mike H
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Re: Sierra 155gn MKBT

Post by mike H »

MR.Sako wrote:first of all your way under the minimum load for 06h which is 43 gr second of all try the 155gr hbc. i have a mate with a howa varmint in 308 that shoots hbc's incredibly well with a 15 thou jump.

Good advice above,what the Hornady projectiles measure has no bearing on what other other brands of projectiles may need to perform at there best.I have shot rifles with more than 50,000" jump successfully.
Dreamcaster51
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Re: Sierra 155gn MKBT

Post by Dreamcaster51 »

Hi MR Sako, a very happy new year to you.
Just a quick one, if i were to load 155gn Nosler CC in my howa with a 15 thou jump they would not be in the shell casing :-)
His Howa must be different to mine, Mine has a very very long throat, even 168gn Sierra match king seated just right have around 70 thou jump.
MR.Sako
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Re: Sierra 155gn MKBT

Post by MR.Sako »

Hi Dreamcaster
the rifle in question if nosler cc or sierra palma matchkings are used the bullet falls out of the case if you were the try and reach the lands but a mob in darwin called optimus projectiles produce a bullet that is 155 grains (http://www.optimusprojectiles.com/ due to the design it tolerates long throats and it will reach the lands in your rifle.
Dreamcaster51
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Re: Sierra 155gn MKBT

Post by Dreamcaster51 »

Hi Mr Sako, Thank you very much for that info. I will have a look on the net and see if I can try some of them. Have a great weekend. :-)
Barossa_222
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Re: Sierra 155gn MKBT

Post by Barossa_222 »

Hi mate. Are you a member of a rifle club? From the sounds of things you could use a bit of a hand learning some reloading basics. You need to find out your maximum first and work back from that. As a rule of thumb with my hunting rifles I've always started 2 or 3 grains under max load in reputable reloading manual and worked up in 0.3 or 0.5gr increments. ADI list a 155gr projectile with 2206H powder at 46gr max load for 2873fps. I would be starting at 43.5gr and working up in 0.5gr increments until I found pressure. For mine I've not used 06H, 2208 gives slightly better velocities with higher case density and slightly lower pressures. Good luck with it.
dgeorge52
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Re: Sierra 155gn MKBT

Post by dgeorge52 »

hi dreancaster...copperhead bullets wodonga vic have 25 sample packs to try if interested visit his site nd have a look...http://www.copperheadbullets.com regards Doug.
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