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lucifers
11-24-2017, 08:30 PM
Don't really want to buy a 300 B/O rifle to shoot heavy cast subsonic lead when I already own a Tikka Target T3 fitted with a can and an NEI 4 cavity 200 gr mould.

Great difference in case capacity could be an issue but there must be a way around that.

Don't wish to reinvent wheel if some have already been down the road.

Thanks folks !

Artful
11-24-2017, 09:16 PM
Get some trailboss powder - start and 11.5 grains and work DOWN - best to have a chronograph
each rifle will have a different friction from the barrel and bullet combination so what works in you T3
may not work in your other rifles.

I usually shoot for about 1025-1050 average with a chrono'd max of no more than 1080.

You will want to shoot first without your can thru cardboard at close range making sure you have nice round holes in the cardboard.

If your boolit won't stabilize switch to a shorter boolit. (weight not the deciding factor length of Projo is)

Once you have a load shooting good groups then put on your can.

You will find the trajectory about like subsonic/standard velocity 22LR ammo.

mulespurs
11-24-2017, 09:55 PM
I would look in the Lyman cast bullet handbook. That ought to keep you busy for a while.

Outpost75
11-24-2017, 11:04 PM
While Trailboss is OK, any fast-burning pistol or shotgun powder will work just fine.

With M80 Ball FMJ bullet lightest charge which will reliably exit the barrel of an M14 or M21 with can attached and spindle value turned off was 5 grains of WC230, which was similar to modern TiteGroup. You could also use 5 grains of Bullseye, 700-X, Red Dot, or similar. In the longer barrel of the M40A1 up the charge a half grain.

Good source for reduced load data is: http://www.gmdr.com/lever/lowveldata.htm

While the above link doesn't have specific .308 Win data, you can interpolate between the .30-30 and .30-'06 charges and stay out of trouble. I don't know what twist your Tikka barrel is, but if it is a standard .308 Win. barrel with 12" twist of rifling it probably isn't going to stabilize a 200-grain bullet subsonic, data below is for a 170-grain bullet of shape similar to #311291 or Accurate 31-171D.

Accurate 31-155D in a 14" twist gives excellent results down to 850 fps. using 3.5 grains of Bullseye.

208403

30-30 Winchester 170gr RNFPbb
PR: WLR CM: Rem TempF: 52 OAL: 2.550"
PT PW Vel SD GS
Bullseye 5.0 990 10.5 2.14
5.6 1071 5.4 1.48
6.2 1146 7.1 2.7
6.8 1201 7.5 2.70
7.4 1263 8.1 3.30

GMDR assumes NO liability for mishaps of any kind resulting from the use or misuse of this data

Artful
11-24-2017, 11:45 PM
You can use other powders but you may have issues, I like Trailboss as it's not prone to detonation or hang fire and not position sensitive.

Some links for you L
http://guns.connect.fi/gow/arcane1.html
http://guns.connect.fi/gow/arcane2.html
http://guns.connect.fi/gow/arcane3.html

https://www.loaddata.com/articles/PDF/LD-36%20Haviland%20LR.pdf

Reddirt62
11-25-2017, 01:34 PM
7.6 grains of Red dot behind a 215 grain Missouri Bullet Company coated projectile works well.

Sent from my SM-N920V using Tapatalk

cavhasbeen
12-02-2017, 02:13 AM
Nose shape also has much to do with stability. I am using the 200gr. Lee mold which is dropping boolits at 194 gr. Completely stable past 550 yds. .308, 1:12 twist 7gr. Red Dot =1070-1080fps. @ 4000' ASL. Is not position sensitive. I would shoot paper out to 100 yds. to check stability before screwing on a muffler. Definitely start higher and work down.Pay attention to loading detail if you intend to play the long game.