Compressed load question

[TheSwede]

Hi!

Just looked in Quickload for a load with N135 powder and was suprised. Wen I reached 105% compressed load I was 3300 bar in pressure and low velocity, max for the caliber is 4050. Is it safe to load 105-110% compressed or should I change powder. The burning rate of this powder should be just right for the bullet so I was suprised.

 

[JimKirk]

I have zero experience with that powder ... but 110% compression is considered the max for many powders(it may be an unwritten rule) ... maybe some one with more knowledge about that powder will chime in ...

 

[Bart B.]

If a drop tube or case jiggling won't compact the powder so it's not compressed, I suggest a different powder.

Compressed loads usually don't have uniform internal ballistics making velocity spreads increase. Sometimes pressures go up as powder particles are reduced in size.

 

[Grumulkin]

Hi!

Just looked in Quickload for a load with N135 powder and was suprised. Wen I reached 105% compressed load I was 3300 bar in pressure and low velocity, max for the caliber is 4050. Is it safe to load 105-110% compressed or should I change powder. The burning rate of this powder should be just right for the bullet so I was suprised.

Several things:

1. I doubt you would be able to seat a bullet and have it stay for long where you seated it with a 110% compressed load; maybe you could at 105%. I ran into a similar issue in loading for a 460 Weatherby Magnum and had to change powders.
2. If your gun magazine allows it, you could seat the bullet a bit further out and thus decrease compression.
3. If you use a case with a little larger volume than what was used to collect the data, the load may be less compressed.
4. I'm skeptical that compressed loads don't have uniform internal ballistics. I would think they would be more uniform as choosing powders that mostly fill a case is what is usually recommended.
5. I guess for powders that have a little hole down the middle of the granules, compression could make the granules smaller. That shouldn't apply to ball or flake powders.

Yea, you should probably change powder.

 

[Walkalong]

1. I doubt you would be able to seat a bullet and have it stay for long where you seated it with a 110% compressed load; maybe you could at 105%

Agreed.

 

[243winxb]

Shape and size have a profound effect on the burning rate and power generation of a powder (Meyer 1987)

http://www.firearmsid.com/Feature Articles/McCord_gunpowder/

N135 , i would not compress. My guess, as its a stick, perforated powder.

http://www.ilrc.ucf.edu/powders/sample_detail.php?powder_id=44

 

[ArchAngelCD]

I also agree you should probably change powder. You should be using a faster powder.

Which cartridge are you loading?