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View Full Version : Phase 1 of my new coyote rifle (pics included)



lungbuster
07-08-11, 15:50
So far my interest in the AR platform has been for the purpose of coyote hunting. (Its about to change as I'm wanting an AR for plinking/carbine courses, but that's another story)

After being a bolt guy, I decided to take the plunge and get an AR. It worked well for me last year on quick follow up shots. The current one I have is an 18" in .223. I decided to let my son use this one for the upcoming fall/winter coyote season.

I wanted a different caliber, so I began doing some research and came across some guys that were using a 6mm DTI with great results. It is a 6.8 case necked down to 6mm and will be fire formed to push the neck to a 30 degree angle. So I will be pushing a .243 bullet faster than my .223. This should help with wind drift.

This upper was built by Mike Milli at Dedicated Technologies. This caliber is his design. He also incorporates an integral compensator to help with muzzle rise.

I call this Phase 1 as this is the new upper however, it is on my current lower. I am going to assemble a new lower (Phase 2) and then have it dipped in camo for Phase 3.

One thing I noticed, is when I purchased a PRI 6.8 magazine, that guys were getting away with longer COAL on these loads. I have some 2.290 COAL so this is a big change from what I was loading for .223


I know most AR's on this forum are of the tactical version, but thought you guys might want to see a different kind.

Anyway, here is the new upper

Specs.

6mm DTI caliber
22" Shilen Select Match SS barrel, hand chambered and profiled
Fully fluted barrel
Custom integral compensator
Mike own free float tube with sling stud.
http://i264.photobucket.com/albums/ii195/beakbuster/DSC09769-1.jpg

http://i264.photobucket.com/albums/ii195/beakbuster/DSC09779.jpg

Integral Compensator
http://i264.photobucket.com/albums/ii195/beakbuster/DSC09772-1.jpg

http://i264.photobucket.com/albums/ii195/beakbuster/DSC09774.jpg

6.8 DTI on Left .223 on right
http://i264.photobucket.com/albums/ii195/beakbuster/DSC09784.jpg

Can't wait to get it out and shoot it.

Warg
07-08-11, 16:25
I'm not sure you need a 6mm to kill 'yotes, but that will certainly work well and is likely to be a great benchrest rifle to boot. You spend lots of $ on that rifle. I'm sure you'll enjoy it.

Indeed, Mike really knows his way around a rifle. I'm having him customize a barrel for one of my varmint ARs.

I realize it’s not a big deal on a hunting rifle, but from your pics it looks like you did not stake the end plate to better secure the castle nut. It's easy to do and worth the added assurance when you're far from home.

MistWolf
07-08-11, 16:54
What bullet weight will you be using with the 6mm DTI and what is it's case capacity? What velocity are you expecting from it? What 223 load are you comparing this to and what velocities were you getting?

Thanks

Cold
07-08-11, 17:01
Nice rifle build, nice optic choice. Well done Sir.

lungbuster
07-08-11, 17:15
Well according to Mike (the builder) and a couple of guys I have been talking to that own the same upper as I do, as far as twist rate, barrel length.


I should get somewhere close to the following. One guy is getting very slightly higher than these velocities.


55 gr Blitzking (BK) should max out at around 3500-3580
60 gr Sierra mid 3300
65 gr Vmax low 3300
70 gr BK 3200 ish
75 gr VMax upper 3080 to low 3150's
85 Nosler Partitin 2900


I plan on trying the 70 BK and 75 Vmax. I purchased dies from Mike a few months ago. Just something with a higher BC that what I'm running in my 223. I would like to stay in the 65 to 75 gr range. Although one guy has told me he has 70 BK loaded for coyotes and then shoots 85 partition for hogs and has had real good success.

I have the following loaded
70 gr Ballistic Tip (BT)
80 gr BT
75 Sierra HP
70 Sierra BK
85 Sierra HP
62 gr Berger
75 gr Vmax

I only loaded small batches as I need to fire form these cases to move the shoulder. Everyone has told me this will tighten up the groups. So I'm gonna play around some.

I'm getting around 2800 fps with 60gr Vmax in my 223. So in theory I could shoot a longer, higher BC 75gr Vmax faster. This should help with wind drift.

But hey, who am I kidding, I wanted a new caliber and this is what I wanted to get. I'll let my son take the 223 and daddy will play with his new toy. I have been talking with a guy in New Mexico that guides for coyotes and has a ranch in Texas that we could shoot hogs. So this would be a fun gun for that.

PM me if you want me to forward you the load data Mike send me.

kartoffel
07-08-11, 20:10
I always admire wildcatters. Even if the cartridge doesn't catch on, it's cool that people keep tinkering and learning. Since this is more of a hobby gun than a life-or-death weapon, why not?

ICANHITHIMMAN
07-08-11, 20:33
2900 from the 85g partition will be murder on deer just murder. Can you pm me a link to the builders site? I want to look into the 6mmDTI a bit more.

chuckocaster
07-09-11, 01:53
very cool rifle dude! 6mm on coyotes will roll em, i've shot a couple with my .243 winchester and had great success with it, fast and clean kills. i used 70-75 grain bullets for that. for larger stuff i use 100 grain.

i just built my first ar, a squirrel gun in 5.56 nato. best of luck with your new gun.

lungbuster
07-09-11, 07:28
Mike has really done a lot with this 6.8 cartridge.

He has a .25 version (he's getting 3000 fps with a 90gr Sierra with an 18" barrel) I'm thinking about ordering one of these

He also has a 6.5 version

He has a .22 version that he's getting about 3,500 fps with a 55 gr bullet

He's investigating a .20 version

Of course he does many other calibers (223, 243 WSSM, 300 Fireball, 204, 6 X 45, to name a few)

I can tell you his work is amazing.

Here's his link
http://www.dtechsuperstore.com/whats_new.htm

Ring
07-09-11, 19:25
my 243wssm... the barrel i had SBN'ed

87gr vamx @ 3150fps
http://i.min.us/jMyM6.jpg (http://min.us/lMyM6)
http://i.min.us/jddXaW.jpg (http://min.us/lddXaW)

lungbuster
07-11-11, 07:18
That is one wicked looking rig!!!!!!!!!!!
Which loads does it like the best?
What kind of speed you getting out of that rig?




my 243wssm... the barrel i had SBN'ed

87gr vamx @ 3150fps
http://i.min.us/jMyM6.jpg (http://min.us/lMyM6)
http://i.min.us/jddXaW.jpg (http://min.us/lddXaW)

Ring
07-11-11, 07:47
will if you go light, like the 57vmax, you can hit 4000fps, but i got it to shoot out to 1k, so i only shoot the 87gr vmax. and that i get 3150 with the load im useing now,

guys with the same gun useing other bullet/powder combos ive seen .25 to .6 at 100y

im getting under 1 MOA right now, but still tweaking the load.

its basically a 243 that fits into a normal AR15 reciver with a bit more FPS, about 100 to 200fps higher.

right now "im on the phone ordering it" im building a 6.5/260rem for out to 1500y

lungbuster
07-11-11, 09:45
When I called Mike at Dtech, I actually ordered a 243 WSSM. Then after talking to him and some other guys, I went with his 6mm DTI. Who knows, I may get a whizzer somewhere down the road





will if you go light, like the 57vmax, you can hit 4000fps, but i got it to shoot out to 1k, so i only shoot the 87gr vmax. and that i get 3150 with the load im useing now,

guys with the same gun useing other bullet/powder combos ive seen .25 to .6 at 100y

im getting under 1 MOA right now, but still tweaking the load.

its basically a 243 that fits into a normal AR15 reciver with a bit more FPS, about 100 to 200fps higher.

right now "im on the phone ordering it" im building a 6.5/260rem for out to 1500y