Hornady 6.5CM factory 147 eld match

[AKMarty]

I shoot a Tikka Tac A1 in 6.5 Creedmoor. It likes the factory Hornady 147 ELD-M cartridges. Shooting 1/2-2/3moa. So I started measuring a box of the factory ammo in order to see what kind of jump I was getting. I was initially looking to see what a good starting point for reloads would be and was surprised by what I found.

Factory CBTO 2.155-2.160”
Factory OACL 2.805-2.809”

I usually have my handloads +\- .001” and am working for a.015-.020” jump to the lands.

This ammo has an average jump of .109”.

Are these crazy numbers or is it in my head?

What do you usually see in your factory ammo? Handloads?

What do you strive for in jump?

Thanks
Marty

PS-I measured each cartridge 2-3x each.

 

[I SHOOT]

Those measurements don't seem to bad for
Hornady factory ammo how consistent are the velocities

 

[supercorndogs]

A lot of people start .02 off as an arbitrary number. A lot of times with a factory barrel the throat is so long, it is not possible to get that close and still feed from a mag. My factory 300WM shot great with jump numbers in the .3 area. Jump isn't something to be afraid of, but if you load them yourself, more people tend to start closer rather than father out.

 

[2aBaC̶a̶]

Makes you wonder if chasing all those .0005 tolerances is even necessary to achieve precise results.

 

[I SHOOT]

A lot of people start .02 off as an arbitrary number. A lot of times with a factory barrel the throat is so long, it is not possible to get that close and still feed from a mag. My factory 300WM shot great with jump numbers in the .3 area. Jump isn't something to be afraid of, but if you load them yourself, more people tend to start closer rather than father out.

True
I've helped a friend work up loads for 2 tikkas 1) tac-a1 and 1) CTR and both had very long throats IIRC he's around .060 jump and they both shoot well.

 

[Rob01]

In my SAAMI freebore chambers I am jumping the 147 ELD factory ammo .090". Measured that just to see where it was as the ammo was very accurate. The 147 is the only one of the ELDs or AMAX I don't load at .020" off. I have them at .030 off so i had plenty of room in the magazine.

Never measured them for any comparison though. I take them out of the box and shoot them. As mentioned it makes you wonder if they shoot that well with the numbers you found if it's worth all the over anal stuff some loaders do. I know my reloading procedures has simplified a lot over the years.

 

[AKMarty]

It’s been -10 to -20 F up here in AK. Waiting for a little warmer weather to get out and use the magnetospeed.

I never thought of going longer.

 

[I SHOOT]

In my SAAMI freebore chambers I am jumping the 147 ELD factory ammo .090". Measured that just to see where it was as the ammo was very accurate. The 147 is the only one of the ELDs or AMAX I don't load at .020" off. I have them at .030 off so i had plenty of room in the magazine.

Never measured them for any comparison though. I take them out of the box and shoot them. As mentioned it makes you wonder if they shoot that well with the numbers you found if it's worth all the over anal stuff some loaders do. I know my reloading procedures has simplified a lot over the years.

True again
I've definitely backed off some of the OCD stuff.
Do my best to find something as close to a 1/2"ish and run with it.

 

[Antero Vipunen]

Found this older thread and noticed OP's observations about freebore jump in TAC A1 6.5.

I have a TAC A1 6.5 with 1200-1300 factory rounds down the pipe. Most of this is Hornady 140gr ELD.
Recently I started reloading experiments and I measured the Tikka chamber. With the same 140gr ELD bullets I'm seeing CBTO of 2.285" when seated 20 mils off lands.

This is about 110 mils more than the CBTO of the Hornady factory ammo using the same bullet.

Now I'm trying to figure if this is throat erosion due to 1200-1300 rounds fired or if Tikkas come from factory with very long throats. Basically I'm trying to determine the barrel wear rate and usable life left in this barrel.

OP, when you measured the 0.109" jump for Hornady 147gr how used was your barrel at that point?

I also sent an email to Sako/Tikka in Finland to ask about throat length when new. Waiting for their answer.

 

[FOHA1]

I have a T3x CTR and it too must have a very long throat. When I measure from jamb, (using the Erik Cortina method), it is substantially longer than factory loaded 147g ELD-M's. Working up loads now, so don't know exactly how far off I'll end up.

Did Tikka ever respond?

 

[AKMarty]

Found this older thread and noticed OP's observations about freebore jump in TAC A1 6.5.

I have a TAC A1 6.5 with 1200-1300 factory rounds down the pipe. Most of this is Hornady 140gr ELD.
Recently I started reloading experiments and I measured the Tikka chamber. With the same 140gr ELD bullets I'm seeing CBTO of 2.285" when seated 20 mils off lands.

This is about 110 mils more than the CBTO of the Hornady factory ammo using the same bullet.

Now I'm trying to figure if this is throat erosion due to 1200-1300 rounds fired or if Tikkas come from factory with very long throats. Basically I'm trying to determine the barrel wear rate and usable life left in this barrel.

OP, when you measured the 0.109" jump for Hornady 147gr how used was your barrel at that point?

I also sent an email to Sako/Tikka in Finland to ask about throat length when new. Waiting for their answer.

1700+ rounds of factory ammo. Most of it Hornady 147 ELDM.

 

[Rob01]

In a SAAMI .199 freebore chamber the oal to lands is about 2.890” to the tip and about a .090” jump for factory ammo.

 

[Dave Collins]

Some interesting info there. Haven't done any measuring on my TAC A1 as to OAL on anything yet. I did buy a box of 140 & 147 Hornady Match, along with Browning w/130SMK and Fed Premium w/130 Berger and Herter's 129gr. The 140 Horn was the best SD of the bunch, 8.6. The 147was the worst, 30.1. Herter's was 2nd best, at 20.?. And yet the FP w/Berger shot the best @ over 20fps sd. Now that I have some fired brass and some of the factory stuff leftover I may have an idea where to start, at least with the Berger's, on a CBTO. be interesting to get a throat length on it and get to work on it.
It was an interesting experiment with the factory stuff, both Hornady rounds were over MOA, the SMK was the worst at about 1.25, Herters was about .8 moa, the FP/Berger was .625 roughly. And of course this was a new gun, trigger at whatever the factory setting was, used the Herter's to sight the scope on paper, cause it was cheap. Got a tall target test done, got a feel for the gun and some idea of what it will do. Most factory ammo I've shot in about 30 yrs or so, velocities were all slower than the box said, 50-125fps except for the Browning, it was spot on at 2900, which surprised me, as the last times I had used factory ammo, it was 125-200fps slow, 125 on a 7-08 and 200 on a 338WM. We'll see how this gun goes I guess, shud be ok to match or beat factory by the look of things. I ended up at 50fps better than factory on the 7-08 and 100fps better on the 338.

 

[Antero Vipunen]

I have a T3x CTR and it too must have a very long throat. When I measure from jamb, (using the Erik Cortina method), it is substantially longer than factory loaded 147g ELD-M's. Working up loads now, so don't know exactly how far off I'll end up.

Did Tikka ever respond?

Just logged in using my password and noticed new messages in this thread.

I haven't received any reply from Tikka/Sako regarding TAC A1 throat length. In their defense, I sent this to generic "info" email address, maybe it didn't get routed to the right person. I will try the phone route (I speak Finnish ).

I just replied to another reloading thread regarding Hornady American Gunner factory ammunition. As I was measuring the Am Gun rounds I realized that it jumps 190 mil in this rifle.

My current handload for this rifle uses Berger 153.5 hybrid seated at 0.100" off lands. Bearing surface connects fully with the case neck without going to the powder column. I'm seeing speed nodes at 2690 and 2790 fps.

 

[clcustom1911]

I shoot a Tikka Tac A1 in 6.5 Creedmoor. It likes the factory Hornady 147 ELD-M cartridges. Shooting 1/2-2/3moa. So I started measuring a box of the factory ammo in order to see what kind of jump I was getting. I was initially looking to see what a good starting point for reloads would be and was surprised by what I found.

Factory CBTO 2.155-2.160”
Factory OACL 2.805-2.809”

I usually have my handloads +\- .001” and am working for a.015-.020” jump to the lands.

This ammo has an average jump of .109”.

Are these crazy numbers or is it in my head?

What do you usually see in your factory ammo? Handloads?

What do you strive for in jump?

Thanks
Marty

PS-I measured each cartridge 2-3x each.

The amount of jump is irrelevant as long as the ammo shoots well out of your rifle. End.

Chasing the lands = chasing your tail when you already have a known load length that works in your rifle. Why discard the length of factory ammo that works just because its not what you "normally" do?

In my T3x Tac A1, I jump my 142 Matchkings at least 0.090" because thats where it shoots the best. Tikka has a really long throat, so seating at the lands only didn't leave me feeling comfortable with the amount of bearing surface in the case neck. So, When I did a seating depth test, I did, 0.030, 0.060, 0.090, and 0.120...

the best groups were between 0.090-0.120" off the lands.

This lines up with the amount of jump with the 147 factory ammo out of your rifle. Coincidence?

Seating depth test interpretations... uh... assistance.

Full disclosure: I've never really done an actual seating depth test before in my 10 years of loading for bolt guns. I've only really tried to duplicate factory match ammo dimensions with better velocity, SD, and ES. It works, but I wanted to actually see what magic could happen. I'm going...

www.snipershide.com

 

[AKMarty]

I ended up abandoning the lands chasing. Getting to the lands pushes the OACL to max magazine length. I did a seating depth test also. First time. I’ll throw my data out here. I expect to get pillaged. Haha.