Sierra 107 TMK

[bfk4lyfe]

You could confirm the node with 29.2, 29.4, 29.6 sets. The if SD's keep in single digits I'd take the 29.4 and, depending on how much freebore you have, 2.250, 2.260 and 2.270 for optimum coal... 29.4, 2650ish and 18" barrel seems to be right in a node-range combo I would expect personally.

ok thanks, i will do just that.

[grayfox]

A low SD (I like <10) and a low ES (prefer in the teens) indicate that the load is exiting the barrel very consistently, which means it should give you good accuracy as well. COAL is the next variable in line to adjust, this tweaks the timing of the bullet exit, so together they should give you an accurate load.

[bfk4lyfe]

A low SD (I like <10) and a low ES (prefer in the teens) indicate that the load is exiting the barrel very consistently, which means it should give you good accuracy as well. COAL is the next variable in line to adjust, this tweaks the timing of the bullet exit, so together they should give you an accurate load.

Makes sense, thanks. It will take a while for me to accomplish all this but I should be able to at least shoot the 29.2,29.4 and 29.6 loads next week. Will report back and then start with the COAL tweaks.

[brut28481]

Anyone try TAC? Sierra's new published load data has that as one of the three powders that gets it going 2700. I am trying TAC after some pressure issues with XBR

[HuntTXhogs]

I have yet to make it out to shoot the TAC loads I made up awhile back.

If it’s not windy or someone is ill or social obligations or....

I’m hoping there is a .75” load in the set otherwise this bullet might become a lightweight Creedmoor load for a bolt action gun.

I wish more folks were trying it out and posting itty bitty groups but it looks like this is going to be a finicky bullet in semi auto (mag length limited) configs

Again I hope I’m wrong ...

[brut28481]

I just ran a break-in load for my new lilja barrel with Tac and the 107 Sierra matchking at 2500 feet per second. Best groups I've got with the 107 yet three or four Cloverleaf groups and that's on barrel break in. I loaded lower charges round 25.7 so it's got a lot of room to go

[Jmccracken]

ill probably pick up some tac at some point and try that as well.

[mdewitt71]

I am interested to hear more about the 107 TMK loads for the Grendel......
Might have to try em out with some 8208XBR, CFE, and Ramshot X-terminator.

[bfk4lyfe]

Little mora data:

Once fired Hornady, Remington 7.5 primers, 8208XBR, 2.258", 65 degrees

29.2: 2638, sd 15.8
29.4: 2655, sd 9.8
29.6: 2673, sd 9.3

All 3" "groups"...will play with seat depth now at 29.4 I guess?

Brass:

[mdewitt71]

Are you saying you shot 3" groups with these 3 loads?

[jason miller]

If anyone wants to sell about 20 of these bullets, let me know.

[bfk4lyfe]

Are you saying you shot 3" groups with these 3 loads?

Yeah, terrible results. I took the scope/mount off and put it on another rifle and shot half inch groups, so I know its not me or the scope, just a bad load.

[bfk4lyfe]

If anyone wants to sell about 20 of these bullets, let me know.

Check your PMs

[Sticks]

I'd be contacting Sierra at this point. That's worse than and undersized Wolf pill with .2 grain variance and inconsistent neck tension. At least those print 1.5" out of a high end barrel.

[mdewitt71]

I'd be contacting Sierra at this point. That's worse than and undersized Wolf pill with .2 grain variance and inconsistent neck tension. At least those print 1.5" out of a high end barrel.

My friend is the lead ballistician at Sierra, I get to go to work often with him.
There is no way that 3" groups are acceptable for any TMK.... I am really surprised from XBR too.

I get Factory 2nds from the back office at Sierra all the time and when I get home and throw them on the scale the most I ever see is .5 grain difference per 100 IF that.

What barrel are you using and did you put this rifle together yourself?
Does it shoot MOA with other loads?
have you tried other powders?