Tikka 6.5 Creed 20" Load data

[Tahoe1305]

Can you help my understanding, does loading long (close to lands) result in more velocity (higher powder capacity?), better accuracy, or something else? I ask because its my understanding that Eldx and Eldm shoot very accurately at factory COAL. I haven't yet measured how much jump this COAL is in my tx3 6.5CM.

On paper, a 20" barrel looks to be better suited for 130 ELDM, 130 MK, or other high BC "lighter" bullets at 2800 fps appears optimal for a 20" barrel tikka inside of 600 yds. I see higher impact velocity, similar energy, and slightly less drop than a 143 ELDX at 2650fps, using Hornady's ballistics calculator. These are ballpark handload speeds for 20" barrel based off what folks have posted online.

I get 2578fps with factory 143Eldx out of my new 20" TX3, which is too slow for my liking. Working up some 143 gr and 130 gr handloads to determine my final bullet choice for hunting.

Effects of Cartridge Over All Length (COAL) and Cartridge Base To Ogive (CBTO) - Part 1

Many shooters are not aware of the dramatic effects that bullet seating depth can have on the pressure and velocity generated by a rifle cartridge. COAL is also a variable that can be used to fine tune accuracy. It’s also an important consideration for rifles that need to feed rounds through a...

bergerbullets.com

Check this out. Written by Bryan Litz and explains it best I think.

Essentially you are “wildcatting” the cartridge a bit seating the bullet out far. This allows for more capacity in the case and typically more velocity. It’s also the reason tikkas (at least in 6.5C) are typically slow loaded to saami limits. There is too much unused volume in the throat. At firing, that volume fills and is inefficient use of the explosion thus comes out slower than you’d expect.

Hope this helps.

 

[Frozenlead]

24” t3x varmint 6.5cm
2683fps
140 Berger EH seated near mag length
43gr N555
White river LRP
Hornady 1x brass
The factory 147eldms run around 2600fps

 

[Andouille]

Effects of Cartridge Over All Length (COAL) and Cartridge Base To Ogive (CBTO) - Part 1

Many shooters are not aware of the dramatic effects that bullet seating depth can have on the pressure and velocity generated by a rifle cartridge. COAL is also a variable that can be used to fine tune accuracy. It’s also an important consideration for rifles that need to feed rounds through a...

bergerbullets.com

Essentially you are “wildcatting” the cartridge a bit seating the bullet out far. This allows for more capacity in the case and typically more velocity. It’s also the reason tikkas (at least in 6.5C) are typically slow loaded to saami limits. There is too much unused volume in the throat. At firing, that volume fills and is inefficient use of the explosion thus comes out slower than you’d expect.

Hope this helps.

Very helpful, thank you. I was unaware that Tikka 6.5cm have long throats, and I measured factory 143 ELD-x at approximately 0.125" jump, so I will start loading at 0.050" jump, which is close to but not at max magazine length. That will gain a small amount of powder volume in the case neck.

Loading long increases the effective powder capacity of a cartridge, which decreases the speed it'll see at any given charge weight but also increases the max speed it can make within a given pressure limit.
....
As for better accuracy, *some* makers will suggest seating close to the lands. But there are tests on several bullets in the last few years that seem to indicate that the best accuracy over the course of a barrel's life, not so much in terms of absolute MOA, but a lack of sensitivity to seating depth as the barrel wears, will occur if you seat maybe 0.050" to 0.100" off the lands. See here:

https://precisionrifleblog.com/2020/03/29/bullet-jump-load-development/

As for 130 versus 147 speeds and which is 'best' at the end of the day it's going to boil down to personal choice. I have seen that I can get 2650' or so from a 20" and 147s and I believe I could get maybe 2725' or so from a 147 if I was willing to fiddle with different powders. But I am not willing to do so. From piddling with GRT it seems as if I could drop to a 130 and get maybe another 125' of MV but over the course of 600 yards you're going to lose all of that advantage, and I rarely hunt in high winds and certainly don't think my kids are ready to take long shots in high winds, so the relative advantages of a fast/light versus slow/heavy bullet are minor, to me. Also, I like long/heavy bullets as a hedge against 'too much of a good thing' with the rapidly expanding match bullets. That is admittedly a personal bias.

YMMV.

Great information, I will start my loading for 6.5CM at 0.050" jump for 143 ELD-X, 130 TMK, and 130 Accubonds. This seems to be a common jump for all three and is likely to put me in a forgiving zone for jump. The powder gain over factory loads is small, with about ~0.060 less jump than factory loads. I hope to gain about 100 fps over factory loads by handloading. I have commonly used H4350, Staball 6.5, Hybrid 100V, and Superformance (last resort) powders on hand, Lapua LRP brass, and match grade primers. Plus I size minimally, only shoulder bumping 0.002" using a bushing die.

To me, the biggest difference between 130 ELD-M and 143 ELD-X is that the lighter ELD-M retains >2,000 fps out to ~600 yds due to the higher muzzle velocity, whereas the ELD-x drops off more quickly and doesn't have an advantage on velocity and drop until out further. My understanding is that 2,000 fps is a very safe minimum impact velocity for both of these bullets. The higher BC of the 143 ELD-x didn't appear to provide a benefit in until well beyond ranges I will shoot animals (<500 yds). In the end, I'll be happy with whichever shoots the best groups at a respectable velocity.

 

[hoooogan]

My first play around loads with 147gr ELDM in my 20" BSF Barrel Springfield Redline with H4350 at 2.800 COAL:
41.0gr - 2597
41.5gr - 2650
42.0gr - 2662

Have a bunch of other stuff loaded for my next trip.
- 127gr LRX at 0.050" jump from 42.5-44.0gr H4350.
- 129gr ABLR at 0.060" jump (mag limited) from 42.0-44.0gr H4350.
- 142gr ABLR at 0.045" jump with 41.0-43.0gr H4350. I'm anticipating ~2700fps at the upper end considering the ELDM speeds at 42.0gr.

 

[AZ_Hunter]

I am a huge proponent of the 130TMK with Staball 6.5. Get higher velocities than other powders like 4350 and my rifle is very accurate with this combo.

 

[Chris in TN]

To me, the biggest difference between 130 ELD-M and 143 ELD-X is that the lighter ELD-M retains >2,000 fps out to ~600 yds due to the higher muzzle velocity, whereas the ELD-x drops off more quickly and doesn't have an advantage on velocity and drop until out further. My understanding is that 2,000 fps is a very safe minimum impact velocity for both of these bullets. The higher BC of the 143 ELD-x didn't appear to provide a benefit in until well beyond ranges I will shoot animals (<500 yds). In the end, I'll be happy with whichever shoots the best groups at a respectable velocity.

Plugging numbers into the Hornady 4dof calculator here.....with a 20" and RL23 (I am personally using RL16 because I am 100% content with the speed/range it gives me for what I will do with this rifle; so this is just academic) and the 147 eldm, at 9000' elevation, I should get around 725 yards before I drop below 2000' impact speed. With the 130 I should get around 800 yards before I drop below 2000'.

Advantage: 130eldm. But only if I was serious about that 700-800 yard window. My chances of taking such a shot with this rifle are virtually -0-. This rifle is much, much more likely to see use at 0-200 yards where I'd prefer the higher SD and lower start speed of the 147eldm to make a longer wound channel.

When the ELD bullets first came out I shot a bunch of deer one fall with the 284"162eldx (mv 3050 or so IIRC) and was really shocked at how little penetration they gave. They were accurate, and at the end of the day it took me a few years to understand and appreciate how well they kill stuff, but I still found them a bit splashy at closer ranges, at least in the context of me always having desired exit wounds for blood trails on whitetails in thick stuff. Erring on the side of the heavier bullets lets me avoid the worst of that 'splash' because they start a bit slower and they have a higher SD. So at the end of the day I see using the heavier bullets as a means to mitigate the worst-case fears of bullets expanding *too* quickly. Is that really a problem at 6.5cm speeds? No. I'll freely admit that. But then again me worrying about which bullet works best at 700 yards isn't a problem either.

 

[Tahoe1305]

Plugging numbers into the Hornady 4dof calculator here.....with a 20" and RL23 (I am personally using RL16 because I am 100% content with the speed/range it gives me for what I will do with this rifle; so this is just academic) and the 147 eldm, at 9000' elevation, I should get around 725 yards before I drop below 2000' impact speed. With the 130 I should get around 800 yards before I drop below 2000'.

Advantage: 130eldm. But only if I was serious about that 700-800 yard window. My chances of taking such a shot with this rifle are virtually -0-. This rifle is much, much more likely to see use at 0-200 yards where I'd prefer the higher SD and lower start speed of the 147eldm to make a longer wound channel.

When the ELD bullets first came out I shot a bunch of deer one fall with the 284"162eldx (mv 3050 or so IIRC) and was really shocked at how little penetration they gave. They were accurate, and at the end of the day it took me a few years to understand and appreciate how well they kill stuff, but I still found them a bit splashy at closer ranges, at least in the context of me always having desired exit wounds for blood trails on whitetails in thick stuff. Erring on the side of the heavier bullets lets me avoid the worst of that 'splash' because they start a bit slower and they have a higher SD. So at the end of the day I see using the heavier bullets as a means to mitigate the worst-case fears of bullets expanding *too* quickly. Is that really a problem at 6.5cm speeds? No. I'll freely admit that. But then again me worrying about which bullet works best at 700 yards isn't a problem either.

I found the eldx don’t like that much speed. Need to impact in the 2800fps or under range to penetrate. They are too soft to impact that fast IMO.

I shot a deer with a 162 going that fast and it made a mess. 175 on elk starting at 2900 is a good recipe for penetration and dead animals.

Furthermore, a 143 going 2800 or so out of a 20” barrel is very effective and will carry more energy than the 130s (although it may not matter)

 

[JGRaider]

IMO a 139 Scenar running 2700' is an almost prefect match for the 6.5CM, much superior to the ELDM and X version from Hornady. So is a 130 AB running 2800.