6.5 CM N555 143 gr. ELD-X

[antunRC]

Hello Guys,

Just seeking for opinion and advice.
I doing load development for my Tikka T3X A1 TAC 6.5CM, which has approx. 1000 rounds through the barrel (my bad I didn't start counting rounds on time).
I have found some N555 powder and Hornady 143 ELD-X bullets. I would like from you guys to give me an opinion on two charts.

I don't have any pressure signs, using once fired Hornady brass, FL sized, trimmed and expanded to .263 with expanding mandrel, primers are CCI 200 LRP. Would you go higher with a powder charge?

Thank you!

 

[BasicMagic]

Hello Guys,

Just seeking for opinion and advice.
I doing load development for my Tikka T3X A1 TAC 6.5CM, which has approx. 1000 rounds through the barrel (my bad I didn't start counting rounds on time).
I have found some N555 powder and Hornady 143 ELD-X bullets. I would like from you guys to give me an opinion on two charts.

I don't have any pressure signs, using once fired Hornady brass, FL sized, trimmed and expanded to .263 with expanding mandrel, primers are CCI 200 LRP. Would you go higher with a powder charge?

Thank you!

What barrel length? Did you note any POI shifts in these shots?

 

[Henryrifle]

@antunRC: Nice rifle. I have had a few just like it. I mostly shot the Hornady 140 and 147 gr. ELD-M but my experience was that those projectiles are very similar to what you are using.

In both of my rifles, the barrels were a little slow. I understand that is common across Tikka barrels.

For 6.5 Creedmoor using the 140 grain class of Hornady bullets, you are going to find a great accuracy node around 2720 to 2750 FPS. That is with H4350 but you are using a powder very similar to that. You should also find a lower accuracy node around 2690 +/- 10 fps.

That said, 42.6 has a nice SD. What is the group size of that load? If that speed meets your requirements and the group size is small and repeatable, you probably have a winner. How many rounds has the barrel shot?

Lastly, what is the main purpose and nominal distance the rifle will be shooting? Guessing hunting by the projectile.

All of the disclaimers apply about working up to those speeds carefully and making sure it works in your rifle. You and you alone are responsible for the results of your hand loading & etc.

Henryrifle

 

[antunRC]

What barrel length? Did you note any POI shifts in these shots?

Original barrel for Tikka T3X A1 TAC 6.5CM - 24". Regarding POI I have it only for today's test with Lapua brass.

 

[antunRC]

@antunRC: Nice rifle. I have had a few just like it. I mostly shot the Hornady 140 and 147 gr. ELD-M but my experience was that those projectiles are very similar to what you are using.

In both of my rifles, the barrels were a little slow. I understand that is common across Tikka barrels.

For 6.5 Creedmoor using the 140 grain class of Hornady bullets, you are going to find a great accuracy node around 2720 to 2750 FPS. That is with H4350 but you are using a powder very similar to that. You should also find a lower accuracy node around 2690 +/- 10 fps.

That said, 42.6 has a nice SD. What is the group size of that load? If that speed meets your requirements and the group size is small and repeatable, you probably have a winner. How many rounds has the barrel shot?

Lastly, what is the main purpose and nominal distance the rifle will be shooting? Guessing hunting by the projectile.

All of the disclaimers apply about working up to those speeds carefully and making sure it works in your rifle. You and you alone are responsible for the results of your hand loading & etc.

Henryrifle

Yes 42.6 has a nice SD. Unfortunately I was not happy with group size and for some reason I had problem with bullet runout 0.003" - 0.005" on most of the reloaded rounds.

My Tikka has approx. 1000 rounds through the barrel (my bad I didn't start counting rounds on time).
Main purpose for load development is hunting and sometimes some match shooting at 300m, 600m and 1000m

 

[antunRC]

So after having a lot of problem with consistency and runout with my Hornady brass I have decided to buy some Lapua brass.
Here is my initial test with Lapua brass:

Bullet was seated to COAL 2.810 (2.066 CBTO) [per Vihtavuori I should seat my projectile to COAL 2.709]
Runout on seated projectile max 0.001" most of them where 0.0005"

I had a lot of struggle with my rear bag. I need to replace that fake sand with the regular one.

Honestly I'm still not happy. I was expecting higher velocity numbers. Usually I was shooting factory ammo (Hornady Precision Hunter 143. gr. ELD-X) and I had best group sizes 1/4 to 3/8" on 100m but now I'm struggling reloading the same projectile.

41.5 had best ES with 2573fps but 41.3 best group size. Any advice and suggestions more than welcome.

 

[Laurie]

N555 is one of several powders I've tried in lieu of IMR and H4350 over the last year in 7mm-08 with the Sierra 160gn TMK. (We have lost all IMR rifle powders in the UK other than the 'Enduron' grades; all Hodgdon 'Extreme' extruded grades; nearly all older pre-CFE Hodgdon 'spherical' powders due to new health & safety regulations.)

N555 showed some promise in this cartridge ...... BUT for my personal interest, after having tried it in standard Lapua large primer brass, I then retried it in my small primer match brass. (This is reformed 308 Win Lapua 'Palma' and fully match prepped including turned necks.)

Results with SP ignition were poor compared to those from near identical LP equivalents other than MVs. ES values and groups both increased. It made me wonder about N555 and SP ignition. Charge weights are greater in the 7mm-08 than in 6.5 Creedmoor, but not vastly.

This report is part of a series I'm currently researching, range-testing, and writing up. The final part (part 3) of the H4350 alternatives including N555 will go up on the blog sometime next week or the one after once I get around to doing the required photography.

Here's the link to Part 1, the introduction to the series.

http://www.targetshooter.co.uk/?p=3..._u4goYlfgXIFvqeNPh2AgMOg0bNRLQHho-vRIm-PiAtfs

 

[BasicMagic]

So after having a lot of problem with consistency and runout with my Hornady brass I have decided to buy some Lapua brass.
Here is my initial test with Lapua brass:

Bullet was seated to COAL 2.810 (2.066 CBTO) [per Vihtavuori I should seat my projectile to COAL 2.709]
Runout on seated projectile max 0.001" most of them where 0.0005"

I had a lot of struggle with my rear bag. I need to replace that fake sand with the regular one.

Honestly I'm still not happy. I was expecting higher velocity numbers. Usually I was shooting factory ammo (Hornady Precision Hunter 143. gr. ELD-X) and I had best group sizes 1/4 to 3/8" on 100m but now I'm struggling reloading the same projectile.

41.5 had best ES with 2573fps but 41.3 best group size. Any advice and suggestions more than welcome.

---

What profile is the barrel? How long between groups?

If you were struggling with the bag are you sure those groups are a good representation of what those charge levels can do?

Any pressure signs on lapua?

With that brass and +saami seating depth I would expect you could reach 2700 at least.

But I do think you have can find a good load between 2550 and 2590 fps. 5 Shots each to better nail down velocity range and a little seating depth testing and you're good. I assume hunting with an eldx bullet. Deer won't tell if the bullet is 100 fps slow at any distance you should be hunting with a 6.5 creed.

 

[Laurie]

Small primer or large?

He's using small primer brass and CCI-BR4s - look at the load details on his attachment on post #6

 

[BasicMagic]

He's using small primer brass and CCI-BR4s - look at the load details on his attachment on post #6

I see it now in the first image. Upon further inspection though his ES numbers look tight enough that I doubt inconsistent ignition is a problem.

 

[Henryrifle]

Quick response: I see that some very knowledgeable folks have weighed into this conversation and when time and workload permit, I will read rather than skim their posts.

Your 41.1 and 41.3 groups and SDs look good to great! The Tikka freebore is V E R Y long. If you are at or near magazine length you are likely jumping .09 or more.

I quickly read something about runout. One of your posts mentions .0005 of runout. I don't have a tool that can accurately measure that but I can tell you that .005 or five thousands of runout isn't going to negatively affect anything in that rifle. Tikka actions are good. The TAC A1 chassis is very comfortable but the action is not glued or even bedded in any way. Make sure it the action screws are torqued correctly and tight.

So, you are shooting great and have some great groups. That will be fine out to 1000 yards. More speed is is good if competing but I'd take the accuracy and good SDs within what looks like a reasonably wide powder charge over extra speed.

I have shot 5-shot groups with Berger 140 VLD-Hunting bullets at 100 yards in the .2s but that's it. Nominal group size was in the high .4s with Hornady 140 class bullets. Hits on steel out to as far as 1300 yards here in low altitude Georgia were reliable on 18" steel with good wind calls.

There are two suboptimal things about your Tikka if it is like mine and the others I am personally aware of. The barrel is slow. Seems common with Tikkas. The freebore is long. Not a big problem but you may want to load closer to the lands and that will often take you to the very edge of Tikka's very good proprietary magazine or just beyond it.

This is just opinion, of course, but you don't have a problem and nice shooting!

Hernyrifle

 

[Gil P.]

Ive been using this powder in a 6.5x47 and am able to get over 2800 fps with 41 gr of Vv N555.

Your velocities seem really slow. I don't have any experience with the 6.5 creedmoor though.

 

[nakneker]

Your numbers aren’t too far off Vihtavuori’s load data.

I tried this powder one afternoon in a 6.5 creedmoor I have, I don’t remember the details but I stopped load development, using Vihtavuori’s load data I was getting a very compressed load and velocity wasn’t that great, I went back to H4350. I’d still like to try N555 in my 7 Saums, I wouldn’t be surprised if it’s a good fit. Seems a bit slow for 143s out of a 6.5 Creedmoor. Take that with a grain of salt, that was my feelings after two hours of playing around.

 

[jepp2]

but I stopped load development, using Vihtavuori’s load data I was getting a very compressed load and velocity wasn’t that great,

That was the issue I ran in to with both the 6.5 CM (Sierra 142's) and my 6 CM's (105 & 115's). So I am back to using H4350 and RL 16 for now.

 

[Gil P.]

Are you guys using drop tubes?

 

[nakneker]

Are you guys using drop tubes?

I didn’t use a drop tube, if the velocity would have been higher, closer to what H4350 is producing, I would have spent more time with it. The main reason I lost interest was the velocity.

 

[Gil P.]

I didn’t use a drop tube, if the velocity would have been higher, closer to what H4350 is producing, I would have spent more time with it. The main reason I lost interest was the velocity.

I use a drop tube and I agree it fills up the case a good amount, but I haven't had any issues getting good velocity.

I think it's a great powder, especially when you can't find varget, H4350, N150 or N550.

 

[antunRC]

I forgot to upload my final load development graph. 44.7 gr. was my final load.
This is way more than what Vihtavuori shows on their website.

 

[Sebrock]

I also found Vhitavouri’s data not even close.

On a 26 inch barrel, Lapua brass, Federal 210m, Hornady 140 grain BTHP, I ran 43.1 grains of N555 with an avg fps of 2850, an SD of 8 and ES of 21. It shot pretty good but was compressed and I felt that the powder didnt like it. Over the next 100 shots I was closer to an SD of 11 and ES of 36 with an FPS of 2841.

I switched to 43.5g of Staball 6.5 and 140g ELD-Ms and that is now my go to in 6.5 creedmoor. 2881 fps, 4.9SD, ES 16.

My barrel is particularly fast. No signs of pressure and have shot hundreds of rounds in both loads described.

 

[darkangel_r2]

I forgot to upload my final load development graph. 44.7 gr. was my final load.
This is way more than what Vihtavuori shows on their website.
View attachment 1295891

Are these charges compressed?

How much neck tension?

What chronograph are you using?

Is anything on your gun during this load development that isn't present when you are shooting for real?

How long can you seat these and reliably feed them?