V-N555 in a 6.5 CM

[stevenedwards]

I am interested in other peoples experience of loading the CM with this "specially for creedmoor" powder.
I can't get the stuff in the case. Vhit. data gives a "full case" load which seems not to be correct, at that load the case is overflowing, what use is that ?
Also I am reaching compression well before the "c" symbol in the load data, close to two grains.
Petersen large primer brass once fired.
The problem is made worse as I'm trying to find a non lead load. copper bullets of around 120gr seem to seat deeper than traditional bullets, particularly the Fox 123gr which appears unusable with N555. Thank goodness for N-150
Ive spent to much time trying to settle the powder by various means to little effect.
Is 120gr copper to big in a creedmoor ?
Rant over. Advice appreciated.

 

[Danny25790]

I've recently got n555 and 120gr hornady GMX, so I am also interested in this as I haven't worked up a load yet

 

[baguio]

Not wishing to sound like I'm teaching you to suck eggs but have you zeroed your scales? I've not had that problem myself. I can only think that you're loading a hot load and seating quite a long way off the lands? Have you tried a longer overall length or just gone straight to 100th or so off the lands?
What powder weight are you trying to fit in and what cases do you have?

 

[paul o']

Lapua L/P Brass Nosler 130 RDF 44G of N555

Sonic toothbrush is what i use with a droptube to settle the powder down ,just sorting out a 9v vibrating pad to place under the load tray .

 

[Laurie]

I am interested in other peoples experience of loading the CM with this "specially for creedmoor" powder.
I can't get the stuff in the case. Vhit. data gives a "full case" load which seems not to be correct, at that load the case is overflowing, what use is that ?
Also I am reaching compression well before the "c" symbol in the load data, close to two grains.

Can't comment on Peterson 6.5mm Creedmoor brass, but in other similar size cartridges, I've found this make to be significantly heavier and also have lower capacity than Lapua equivalents (as used where available in all Viht loads). In 260 Rem and similar, I drop my Lapua max charge by 1gn for Peterson. Remember, when you see factory loads data, it is only valid for those exact components.

Use a drop tube too as @paul o' suggests. In cases of this size, a slow and angled swirl-pour using the Forster Universal Funnel with its 5.5-inch tube has approximately the same effect as a 1gn charge reduction on powder level position.

 

[stevenedwards]

Not wishing to sound like I'm teaching you to suck eggs but have you zeroed your scales? I've not had that problem myself. I can only think that you're loading a hot load and seating quite a long way off the lands? Have you tried a longer overall length or just gone straight to 100th or so off the lands?
What powder weight are you trying to fit in and what cases do you have?

Hi ive checked the load weight with a second scale.
As i am trying to load Satterlee tests I have settled on 50th off to start with.
I am trying to load a progression up to "book" max 44.6 but just can't get there with out several increments being compressed when the Vhit data says they should not be.

 

[stevenedwards]

I've recently got n555 and 120gr hornady GMX, so I am also interested in this as I haven't worked up a load yet

This is exactly the combination I was trying.

 

[stevenedwards]

Lapua L/P Brass Nosler 130 RDF 44G of N555

Sonic toothbrush is what i use with a droptube to settle the powder down ,just sorting out a 9v vibrating pad to place under the load tray .

Good idea, I am just about to try the tooth brush

 

[stevenedwards]

Can't comment on Peterson 6.5mm Creedmoor brass, but in other similar size cartridges, I've found this make to be significantly heavier and also have lower capacity than Lapua equivalents (as used where available in all Viht loads). In 260 Rem and similar, I drop my Lapua max charge by 1gn for Peterson. Remember, when you see factory loads data, it is only valid for those exact components.

Use a drop tube too as @paul o' suggests. In cases of this size, a slow and angled swirl-pour using the Forster Universal Funnel with its 5.5-inch tube has approximately the same effect as a 1gn charge reduction on powder level position.

Hi Laurie
I will try with Starline and some Hornady I have.
Do Blaser chambers measure short as none of the copper bullets I have tried can be loaded out to the specified max.OAL

NBT 120gr does not give me this problem as it loads longer.

 

[Bowland blades]

Just remember 5 series powder burns your barrel out faster it might not actually give you any more velocity I many barrels . I won't use the stuff ,

 

[baguio]

Just remember 5 series powder burns your barrel out faster it might not actually give you any more velocity I many barrels . I won't use the stuff ,

How do we know which powders are series 5? I'm using Lapua SP Creedmoor brass BTW.

 

[Bowland blades]

How do we know which powders are series 5? I'm using Lapua SP Creedmoor brass BTW.

A vhit powder number that starts with a 5 is a 5 series powder . They burn very much hotter as they are double base
140 , 150 , 160 , etc are not 5 series

 

[baguio]

A vhit powder number that starts with a 5 is a 5 series powder . They burn very much hotter as they are double base
140 , 150 , 160 , etc are not 5 series

Thank you and sorry, it appears rather obvious now. I hadn't realised it was only in relation to vhit powders. Doh!

 

[paulux]

Do Blaser chambers measure short as none of the copper bullets I have tried can be loaded out to the specified max.OAL

I've had the same issue with a Blaser K95 6.5x55 barrel and Fox lead free 139 gr bullets.
When seated at the COL specified by Fox (77.5 mm), the cartridges would'nt fit in the chamber. Went down to 74.63 mm COL.

 

[stevenedwards]

Starline brass seems to give almost half a grain improvement in capacity over Peterson. My measurements may not be perfect !
I will try the Hornady tomorrow

 

[Laurie]

Just remember 5 series powder burns your barrel out faster it might not actually give you any more velocity I many barrels . I won't use the stuff ,

This applies to most N500 series powders, but N555 has a low specific energy rating compared to its siblings. Look at the table here:

https://www.vihtavuori.com/powders/n500-powders/

3,700 J/g is identical to Viht's energy rating for N140 as seen in the equivalent table for the N100 series.

Even with the hotter burners, barrel wear will only increase when cartridges are loaded to full pressures. A good N500 load can often provide the desired MV at lower pressures than from its 100-series equivalent. Equally, you can burn a barrel out quickly with N100 series powders with the combination of heavy bullets and very heavy loads / pressures. The load in 308 Win F/TR with heavy (>185gn) bullets these days is a small primer Lapua or Peterson case-full of N150. Performance is superb, but the cost is a 2,000 round (stainless match) barrel life, less on occasions. On the other hand I loaded modest pressure 155-175gn N150 loads in equivalent barrels for many years in 308 Win and barrel life was very good. An old F/TR shooting friend has loaded Viht N550 and the old 210gn Berger LRBT to 'warm' but not OTT-pressures in 32-inch stainless barrels for over 10 years and his barrel life is good, even if not as good as I got with mild N150/155gn combinations.

 

[Bowland blades]

Thank you and sorry, it appears rather obvious now. I hadn't realised it was only in relation to vhit powders. Doh!

Other manufacturers use double base also coded or named differently

 

[Laurie]

Other manufacturers use double base also coded or named differently

Post Reach, over three-quarters of available powders are either double-based or 'high-energy'. Technically, the latter remain single-based as the early stages of manufacture don't use nitroglycerin and the 'base' bit refers to the initial formulation, but it is then infused into the kernels at a late stage. This is the technique used in Reload Swiss 'EI' grades - RS40, 52, 60, 70 and others and all Viht N500 series.

All ball powders are double-based and all recent tubular / extruded introductions likewise - eg the five Reach-compliant IMR 'Enduron' grades, new Alliant numbers, Viht additions, the entire reintroduced to the UK Norma range, Ramshot etc, etc. It is obvious that this is the way the industry is going. There are no doubt benefits in use of nitroglycerin, especially to military purchasers who are the drivers of R&D and new products in the field - stability, long-life and temperature stability are now key requirements. No longer are double-based products automatically more temperature affected than single-based as Recent introductions such as the Bofors manufactured Alliant 'TZ' grades are claimed to be better than the past leaders, Hodgdon's 'Extreme' grades.

The sole remaining single-base / no added nitroglycerin rifle powders left are Viht's large and excellent N100 series, and Lovex SO designated extruded tubular powders, plus maybe some Vectan tubular 'Tu' numbers if they're still available.

There is 'double-based' and double-based' of course in that nitroglycerin levels vary a lot between makes and grades. Few companies divulge the levels, but Norma which has long done so shows some of its grades are way down at around 4% whilst c. 10% will be common in many other examples and the 'hottest' powders in its range are around 14%. Many years ago, I bought a recently rebarrelled 7.62 TR rifle and worked an Alliant Reloder 15 load up for it with the original 155gn Sierra Palma MK bullet. As I only shot to a maximum of 600 yards then, and more often than not 300, it didn't need a heavy load and high MVs, just good precision so it was a moderate pressure/speed combination. After around 1,000 rounds use I sold the rifle to a fellow club member and see it regularly when I go that club and range with it still in regular use today 20 plus years on with the same Maddco stainless barrel on it. The new owner adopted my load and still uses it. I reckon that barrel has had at least 5,000 rounds down it now and he tells me it still shoots exceptionally well. Alliant Re15 is to all intents and purposes relabelled Norma 203-B which Norma lists as 7.5% nitroglycerin by weight.

 

[stevenedwards]

In the light of the responses i have just un-packed the 120 GMX rounds loaded. It may just be a lack of knowledge on my part but I was a little alarmed at how hard packed the upper half of the ladder test was. The powder had to be teased out and the highest load was below the Vhit data "compressed" level.
Trying to run 120/123gr. copper in a Creedmoor may not be feasible and I should be looking to 100/110 gr. bullets. I am looking to achieve sufficient velocity to give some expansion up to normal ranges with sensible pressure levels, as no doubt others are.
This is not a problem I have had with the 243, Yew Tree 80gr and N160 job well and truly done, simple !!
Smaller weights of n-100 series feels preferable to more 5 series and having to use a ram rod to try and get enough in
Thanks again for the input

 

[stevenedwards]

I forgot to say I have not had any problem loading real bullets in the Creedmoor. NBT 120's and Sierra pro hunter 120 work particularly well in my rifle.