New 6 arc build underway - ltwt mnt rifle

[hiaring8]

New to the forum and new to the 6 arc. Have hunted all over the west and the backcountry of my home state of Idaho, and over the last couple of years have become more and more of a believer in smaller cartridges for hunting deer, elk, antelope, bear, etc - basically anything in the lower 48. Retiring the large rifles (7 rem mag, 300 rum) for a while and decided this is the year I build a smaller, lighter, rifle for my backcountry hunts. My wife and daughter shoot a 6 creed and 243 respectively (108 ELDM, 105 scenars, 95 NBT) and always amazed what those bullets did on game, so after much research, settled on the 6 arc.

Here is the list of the parts - right now I am only missing/waiting on the stock then can put everything together and start load development - HOPING TO HAVE STOCK WITHIN NEXT COUPLE OF WEEKS. 

Howa Mini Carbon Fiber Barreled action - 20"
JO Outdoors BDL Bottom Metal
Timney 611 trigger - set for 2.5 pounds
Stockys CF VG Desert Sagebrush Stock
Backcountry Banish Suppressor
Burris XTR steel 2 piece pic bases
Warne Mnt Tech Low Rings
SWFA SS 3-9X42 Scope

Will have action glass bedded, and barrel floated in stock. I do want to make this as bomb proof as I can, so probably will have the bases bonded to the action. Also probably going to have Kampfelds replace the factory knob with one of his campfire knurled knobs. Based on the parts I have in and an estimated 21-22 oz of stock and say 2-3 oz of bedding material weight - this rifle should finish up around 7 pounds 3-6 oz. Should be a perfect little backcountry mountain rifle and will save me almost 2 pounds off the custom 7 rem mag that I have carried the last few years...

I have a bunch of Midway 2nd 106 TAPs that I will shoot. They are a bit tougher than the ELDMs so I am upping my velocity threshold for expansion from 1800 FPS to a minimum of 1900 FPS for the TAPs. I should be able to get a good load atleast at 2750 FPS, best case goal 2775-2800. (Lever and H4895). But 2750 will get me out to about 700 yards with this little rifle.

As it comes together and I am able to shoot it and get data, I will load pics and information.

[300BLK]

New to the forum and new to the 6 arc. Have hunted all over the west and the backcountry of my home state of Idaho, and over the last couple of years have become more and more of a believer in smaller cartridges for hunting deer, elk, antelope, bear, etc - basically anything in the lower 48. Retiring the large rifles (7 rem mag, 300 rum) for a while and decided this is the year I build a smaller, lighter, rifle for my backcountry hunts. My wife and daughter shoot a 6 creed and 243 respectively (108 ELDM, 105 scenars, 95 NBT) and always amazed what those bullets did on game, so after much research, settled on the 6 arc.

Here is the list of the parts - right now I am only missing/waiting on the stock then can put everything together and start load development - HOPING TO HAVE STOCK WITHIN NEXT COUPLE OF WEEKS. 

Howa Mini Carbon Fiber Barreled action - 20"
JO Outdoors BDL Bottom Metal
Timney 611 trigger - set for 2.5 pounds
Stockys CF VG Desert Sagebrush Stock
Backcountry Banish Suppressor
Burris XTR steel 2 piece pic bases
Warne Mnt Tech Low Rings
SWFA SS 3-9X42 Scope

Will have action glass bedded, and barrel floated in stock. I do want to make this as bomb proof as I can, so probably will have the bases bonded to the action. Also probably going to have Kampfelds replace the factory knob with one of his campfire knurled knobs. Based on the parts I have in and an estimated 21-22 oz of stock and say 2-3 oz of bedding material weight - this rifle should finish up around 7 pounds 3-6 oz. Should be a perfect little backcountry mountain rifle and will save me almost 2 pounds off the custom 7 rem mag that I have carried the last few years...

I have a bunch of Midway 2nd 106 TAPs that I will shoot. They are a bit tougher than the ELDMs so I am upping my velocity threshold for expansion from 1800 FPS to a minimum of 1900 FPS for the TAPs. I should be able to get a good load atleast at 2750 FPS, best case goal 2775-2800. (Lever and H4895). But 2750 will get me out to about 700 yards with this little rifle.

As it comes together and I am able to shoot it and get data, I will load pics and information.


If you subsititute the SWFA ultralight 2.5-10x for the SS3-9x42 you'll save at least 10oz!  I've shot a rifle with the 2.5-10x and was favorably impressed, have SS6x and SS10X on a couple of my own rifles.

[grayfox]

The overall rig sounds very nice. A little tempering of expectations, though... I would not get hopes up for 2750 from a 20" barrel, especially from H4895. I like H4895 a lot but it is not the optimum powder for the heavier weights/longer bullets like a 106. Hornady has a 27.2 gr limit for H4895/bolt action 108's, which for a 20" might get you in the 2600's. A powder like lever might get up to those mid-upper 2700's; I have not taken lever up that high for 103's/105's/107's) but for the longer bullets you might be running out of case room. Do careful workups whatever your choice of powders.
Of course hunting in Idaho (love that state by the way!! I was there back in the 70's) at elevations your ballistics will travel farther than at lower, 0-500 ft elevations ASL. With lever and a 103 eldx at those elev's, I could estimate 1000 ke range out to 450-500 yds from a 2750-ish MV. For a TAP, you could push that out to 550 yds. But not at 0 degF, IMO.
Anyway, great setup, let us know how it does when you get it all assembled.

[hiaring8]

Yes, 106 is long, and while I have lots of h4895, lever will probably end up being my go to powder to hopefully get to where I want to be. I have read people having some issues getting the TAP to shoot well so thats a bit concerning. The TAP is a very long bullet and if it doesn't work out as I want, I will look at the 103ELDx and 105 scenar - killed lots and lots of critters with 139 and 150 grain scenars in other calibers - im sure the 105 will kill great as well. It just has a lower BC and probably limit my distance reliable expansion velocity. Berger 108s may get a look as well.

Either way, I think this rifle will make a great ltwt backcountry gun and with suppressor and small case/powder capacity, hopefully be a very quite rifle. I have been with buddies who have shot animals with suppressed medium rifles (260, 6.5, .308 ETC) and I would be just over the ridge and could hardly hear the shot.