6.5 CM with Viht N550........any recipes?

[Scapegoat]

Here goes, another 6.5CM reloading thread...... however, my google-fu is weak, and although I can find all sorts of recommendations for using N550, I can't find any data for loading my bullet of choice.

I have some Starline LRP brass, CCI primers, and want to load some ELD-X 143 grain bullets. I've shot the factory loads from Hornady (Precision Game) and love the groups and the results (two nice Roe and a couple of foxes so far).
Rifle is a Tikka T3X CRT with a 20" barrel,
I want them for recreational range work as well as stalking/foxing, so although I want an accurate, dependable round, I'm not yet looking at Bench Rest performance.
Next, I would like initially to go for accuracy over velocity, as I have stuck with this mantra with considerable success with previous loads for .243 and .308, but I'd also like to be able to stretch the round as far as my scope will allow on occasions.

The Viht data gives loads for 144 grain FMJBT, Lapua starting at 31.3 gr and goes up to 37.7 gr, which gives a velocity more or less in line with the factory Hornady rounds. It also gives data for 140 gr Accubond bullets, also a boat tail, of between 32.1 and 38.3. There is a bit of variation in the other two or three 140 gr rounds shown on their cart, with lows of 30.5 and highs of 39.0 (Berger)

My thoughts, unless anyone tells me I'm going to end up with a nightmare, would be to start between the highest low, and the lowest high and work carefully upwards. Any pitfalls,

TL, DR; has anyone loaded 143 ELD-X with N550 and can tell me where to start?

 

[EQUADIF68]

Hi Scapegoat ! I do suppose you mean reloading 6.5 mm ?

 

[Malxwal]

Hi Scapegoat ! I do suppose you mean reloading 6.5 mm ?

6.5CM = 6.5 Creedmoor.
Have run N550 behind 123 and 129 Hornady SST, with great promise, but havent done full load work, and its only for stalking.
I have no doubt Dodgyknees will be along, an authority on 6.5 Creed and 143 ELD-X.

 

[Spiker]

I have spent a very long time load dev my CM. Tried N550 and reverted back to N150. Accuracy, low recoil and gets to 1000yards which wasn't the ultimate aim of the development. Had accuracy issues with ELD's and now use Scenars with unbelieveable accuracy. The Scenars were cheaper as well. Tried the ELD's in .260Rem and had identical issues. Good luck.

 

[Muir]

Here goes, another 6.5CM reloading thread...... however, my google-fu is weak, and although I can find all sorts of recommendations for using N550, I can't find any data for loading my bullet of choice.

I have some Starline LRP brass, CCI primers, and want to load some ELD-X 143 grain bullets. I've shot the factory loads from Hornady (Precision Game) and love the groups and the results (two nice Roe and a couple of foxes so far).
Rifle is a Tikka T3X CRT with a 20" barrel,
I want them for recreational range work as well as stalking/foxing, so although I want an accurate, dependable round, I'm not yet looking at Bench Rest performance.
Next, I would like initially to go for accuracy over velocity, as I have stuck with this mantra with considerable success with previous loads for .243 and .308, but I'd also like to be able to stretch the round as far as my scope will allow on occasions.

The Viht data gives loads for 144 grain FMJBT, Lapua starting at 31.3 gr and goes up to 37.7 gr, which gives a velocity more or less in line with the factory Hornady rounds. It also gives data for 140 gr Accubond bullets, also a boat tail, of between 32.1 and 38.3. There is a bit of variation in the other two or three 140 gr rounds shown on their cart, with lows of 30.5 and highs of 39.0 (Berger)

My thoughts, unless anyone tells me I'm going to end up with a nightmare, would be to start between the highest low, and the lowest high and work carefully upwards. Any pitfalls,

TL, DR; has anyone loaded 143 ELD-X with N550 and can tell me where to start?

Use the 144 grain data, starting at the minimum charge. ~Muir

 

[Scapegoat]

6.5CM = 6.5 Creedmoor.
Have run N550 behind 123 and 129 Hornady SST, with great promise, but havent done full load work, and its only for stalking.
I have no doubt Dodgyknees will be along, an authority on 6.5 Creed and 143 ELD-X.

Hope so, looking forward to a few hours in the shed!

 

[Lateral]

I run RS60 with the ELD-X 143, appears to be very similar to the N550. I'm getting 2875fps with 42gn's, but I have no idea how the case capacity of the two different cases compare. 2.825" OAL.

My initial load was higher, but accuracy went off, and velocity increased, after putting a number of rounds through, so I dropped it back, until I got circa 2875fps again, and it's back to where it was.

Top left shot, cold clean barrel. Then a 3 shot group. 100yds.

 

[Edinburgh Rifles]

By coincidence I have been working up some data for customer today
All theoretical based on 24" barrel run through Quikload
COAL is set slightly longer at 2.874"/73mm
Case is 53.5gr H2O
Load for 136gr Lapua Scenar-L

RS60 looks very promising

 

[Scapegoat]

Thanks ER!

A propos COAL, does anybody have any thoughts or recommendations on jump space for the Tikka chambers? ? I loaded my .243 very close with great results (.020"), and load my .308's as long as the mag allows (getting on for 60 thou) , again with results good enough for stalking purposes.

So, again, where to start?

 

[Lateral]

I would start with the manufacturers suggestion, and see what happens.

The bottom line is, you can get a gazillion suggestions on here, and none will work, or maybe one will, but by the time you've tried them all, you could have worked a load up.

There are so many variables, case, barrel length, even the tolerance of the barrel ID, you're better off just getting on with it.

 

[JTO]

Is N550 considered to be a high energy(Hot) powder?
Cue Laurie re barrel life if used for range work.

 

[Edinburgh Rifles]

N550 is a double base/high energy powder
barrel life is as much a function of frequency and style of shooting (strings of 20 run hot, some plinking with cool down)

Start and stay at Factory OAL, no factory rifle needs land busting rounds to be more accurate than you are.
practice the fundamentals before you tweak OAL
if you have inaccurate homeloads its highly unlikely it is solely down to OAL
you will get more variance from neck tension than most other aspects

 

[army-medic]

I could not get a good load with N550 and stared using RS62 instead.

Much better with little effort. RS60 is quite hot and may be a barrel burner.

If you look at the reload swiss website you will find some load data. If you click “customer
Data” you get more results.

 

[Scapegoat]

Is N550 considered to be a high energy(Hot) powder?
Cue Laurie re barrel life if used for range work.

I thought if you said Creedmoor three times in a post he appeared anyway!

Is disappoint......

 

[6.5Guy]

practice the fundamentals before you tweak OAL
if you have inaccurate homeloads its highly unlikely it is solely down to OAL
you will get more variance from neck tension than most other aspects

Pretty good point from ER.
I'm working up a target load 6.5CM N550 load at the moment for my t3x tac a1 using hornady eld match 140gr. I Started with the low end charge for the 147gr I believe.
I measure OAL using a hornady gauge and then take it back 20 thou and won't touch it again until I've found the approximate charges I want to work with further (low sd) then I'll start messing around with how far or close to lands it is.

I was a squeak underwhelmed with my first tests on N550. Fps was a little lower than I'd hoped although the sd was good.
On the plus side though that means I have to go to the range again!

 

[Scapegoat]

Pretty good point from ER.
I'm working up a target load 6.5CM N550 load at the moment for my t3x tac a1 using hornady eld match 140gr. I Started with the low end charge for the 147gr I believe.
I measure OAL using a hornady gauge and then take it back 20 thou and won't touch it again until I've found the approximate charges I want to work with further (low sd) then I'll start messing around with how far or close to lands it is.

I was a squeak underwhelmed with my first tests on N550. Fps was a little lower than I'd hoped although the sd was good.
On the plus side though that means I have to go to the range again!

Pretty much underwhelmed with N550 certainly in terms of velocity.
Loaded between 35.5 and 37.5grain, col of 40 thou less than touching. (Thought I'd gone mad, but the chamber in the CTR is a whopping 2.298")

Ladder tests with a chrono gave me very tight groups with 36gr, 36.5gr, 37 gr and 37.5gr. The chrono was being temperamental, and I got data for the 37 and 37.5grain loads only, averaging 2349, with an SD of 9.7 for the 37gr, and 2394.2 with an SD of 12 for the 37.5

For comparison, through my 20" barrel, factory 140 ELDms gave 2726 with an SD of 42.7, and 143 gr ELDx factory rounds 2560, SD 38.2. Both printed slightly larger groups.

So, Viht's highest recommended load gives a MV well below factory rounds. Accuracy is not an issue. What would the assembled masses do? There are no pressure signs at this load, do I push on carefully in 0.5gr increments to try and increase the MV or do I try a different powder?

 

[Malxwal]

No chrono data, and lighter bullet, so perhaps a bit irrelevant here, but....
Running 123 SST loaded to 2.830, about .020 off lands,over 44.4gr N550, SR Lapua brass, 24" 1 in 8 barrel. Absolutely zero pressure signs.Rifle is zeroed bang on at 100m, and vapourises crows at 250m aiming at the head. Extremely unscientific until we both get time to do more detailed load work.

 

[GregorG]

Maybe irrelevant.

Fox bullets 123gr, N550 41.0 grain, lapua SR brass, murom KVB-223... no pressure signs.
Tikka CTR 24"

Dropbox

www.dropbox.com

 

[Mick Miller]

I found N550 extremely temp unstable. RS62 a much better bet.

 

[Scapegoat]

I've settled on a 38gr load. It's grouping under .25moa @100 yards and giving 2450 fps or thereabouts, with no pressure signs. They'll do for the time being, and will do me for foxes, does and plinking.

I'll use the rest of the half-bottle of N550 and then move onto something else as I get out onto longer ranges in the spring/summer. I now know several folk using RS62, so that'll be my next project.