How low can you go?

Status
Not open for further replies.
J

JacobZ

Member
Joined
Jun 24, 2014
Messages
1
Location
Northwest Europe
This is not a question about shuffling one's belly under a batton. But can anyone help me on loading data for a FMJ round of 140gr to be fired from a 1916 Carl Gustav 6.5x55se, ordonnance rifle, 30" barrel. I have gun powder Vithavuori N150 available; And I have the Vitha tables. To be more precise. I want to fire them at a target at 100m or 300m. The Lapua table says: 32.1gr-36.4gr. N150 is a slow burner, comparable to R904, Tubal5000 or H4350

I don't need going ballistic. I only need accuracy.
In other word how low can I go beneath the starting load as suggested in the Vita tables... before I start piling up bullets in the barrel or get all the economics of reloading in my face?
 
Welcome to the forum....

With most smokeless powders, especially the slower ones, will not produce acceptable results unless you load them in the upper regions of the load data. Sometime you will get erratic powder burns, incomplete burns, wide swings with the ES (extreme spread) numbers and more. I'm not saying all that will happen if you load light with all powders and I'm not saying it will even be very noticeable but those things can happen.

The companies who supply load data give you a starting charge weight and a Max charge weight and for good reasons. It's usually a very good practice to stay at or above the starting charge weight, not below.

Please don't forget the range report...
 
You have a fine rifle. Like R.C. said you'll be fine at listed starting data.

I'm sure it is difficult to cross reference the data we have in the U.S. to the stuff in Europe. Some of the powders are the same but have different names and others are different all together.

And you really don't want to use a reduced charge(lower than listed start) of a slower powder either just as Arch stated.
 
You should not ever go below minimum. Below minimum loads can be as dangerous as above maximum loads. Causes weird pressures and can cause the powder to detonate instead of burn.
You need to work up the load, using data from your manual, beginning with the starting load and going up by half a grain until you get to the max load. You'll likely find the best accuracy somewhere in the upper half of the loads.
Your M96 didn't use a 140 until 1941, but look for a load that give around 800 m/s (2,625 ft/s).
 
With most rifle powders, and especially slow burner's, accuracy is not usually found below the charge tables.

Is there some particular reason your wanting to drop charges below published data?

Most accuracy is achieved in the mid to upper end of the tables with slow burner's.

GS
 
Certain powders have published data or methodologies for developing light, safe loads. Check out H4895 and Trail Boss. Another one to check out is SR 4759, but you'll need to look for older data.
 
John C said:
Certain powders have published data or methodologies for developing light, safe loads. Check out H4895 and Trail Boss. Another one to check out is SR 4759, but you'll need to look for older data.
Click to expand...
Yes, H4895 (AR2206H) is a very good powder for making reduced rifle loads.
Here is the reference page which contains some data and the formula for reducing the powder charges safely.
http://hodgdon.com/PDF/H4895 Reduced Rifle Loads.pdf

I'm not crazy about using Trail Boss in rifle cartridges and it should be used with lead only. It makes very good low velocity Cowboy action handgun loads but not so good with the rifle, only IMO of course. SR-4749 is a very good powder for reduced loads but it is scheduled to be discontinued at the end of 2014.
 
I'm not crazy about using Trail Boss in rifle cartridges and it should be used with lead only.
Click to expand...

Hogdon says:140 GR. SFT-Manufacturer IMR Powder Trail Boss Bullet Diameter .284" C.O.L. 2.750" Starting Load Grains 11.0 Velocity (ft/s) 1,211 Pressure 36,200 CUP Maximum Load Grains 16.0 Velocity (ft/s) 1,472 Pressure 43,300 CUP.This is from the Hodgdon site and this data is NOT for use with 6.5x55

It was developed for cowboy loads in .45LC and such but there is now data for jacketed rifle. ;)
 
Last edited:
Archangel, I have no direct experience with Trail Boss in rifles, but I intend to correct this deficiency this summer. A reloader I know and trust has had excellent results with 110 gr jacketed RN carbine bullets and 150 gr jacketed FP over a case full of Trail Boss in .308 and .30-06. His experience is that Trail Boss works best in rifles at 100% load density, uncompressed, of course. I intend to try this out for myself, along with some AA 5744 that I traded in to.
 
It seem Hodgdon has added Trail Boss to the powder list for jacketed bullets in some cartridges. It looks like Hodgdon is using TB with only light for caliber bullets of in only one load per cartridge. I guess I'm old fashioned but I am always a little worried when a company tells you not to use a powder with jacketed bullets and then changes it's mind.

Do what you will but I won't be using Trail Boss with jacketed bullets, especially in rifle applications considering there are other options.
 
before I start piling up bullets in the barrel or get all the economics of reloading in my face?
Click to expand...
If you are looking at downloading for the economy, -- I urge you to work the math at just how little the $$ difference between the low to high range is for the powder charge.
For your N150 the charges of
32.1gr-36.4gr.
Click to expand...
equate to a 4.3gr range. I don't know how much the powder will cost you where you are in Europe, but using US $ pricing -- assuming around $30 a pound for it, that's only a difference of $0.01842 between the low and the high range. That's less than 2 cents. Your thoughts on the economy of loading are good, but I think you need to look at other areas to maximize the savings benefits and stay safe.
For the math side price of a pound of powder divided by 7000 (grains to pound) multiplied by 4.3.
 
Let me just say this:
Always starting at the starting load is correct, but the starting load is not the minimum load. It is no more than what the people writing the manual assume is a safe load. It may be simply a 10-12% reduction from the max charge. It may simply be down to a pressure they want to use for all starting load. In some cases, data is listed by velocity and the starting loads are at their selected starting velocity. In no case does this mean that it is a minimum load.
Next, twice when I first started reloading (back in the '70s), the starting load I used was near max or even over max in MY gun. Thus, I have always checked at least two independent sources and started at the lowest starting load. Never had a near-max starting load since.
If starting loads were minimum, then many/most Bullseye competition loads would be unsafe and many action pistol minor power factor loads would be unsafe.
Trail Boss will produce very mild loads in all rifle cartridges.
 
Status
Not open for further replies.
Back
Top