Why are triple base propellants not used in firearms?

[chemisthypnos]

I would think that the use of triple base propellants in hand-held weapons, such as assault rifles or pistols, would be greatly beneficial as its use would remove the muzzle flash. Also, it would decrease wear-and-tear on the weapon itself, I would think. I have found some people saying that triple base propellants are only used in heavy weaponry (such as for tanks or naval vessels) due to the scarcity of nitroguanidinium https://fas.org/man/dod-101/sys/land/bullets3.htm . Does anyone know why, generally, only single base propellants are used for assault rifles and pistols?

 

[trurle]

You can use triple-base propellant for pistols, not problem at all. It just makes no point because erosion of small barrels is already low, and low-caliber barrels themselves are cheap. It is more economical to replace barrels of firearm periodically rather than to have higher paycheck for ammunition..

 

[chemisthypnos]

The erosion of the barrel would be a secondary concern at best. The ability to hide the muzzle flash, however, I would think would be a convincing reason to use the tripple base propellant over single or double base propellants.

 

[trurle]

The erosion of the barrel would be a secondary concern at best. The ability to hide the muzzle flash, however, I would think would be a convincing reason to use the tripple base propellant over single or double base propellants.

Good Shooter = Experienced shooter = A lot of cheap ammo
Reducing a muzzle flash have actually very limited merit. Among army officers, i heard a lot about recoil and handling specifics but not much about muzzle flash. I think muzzle flash reduction is meritous to very specialized forms of engagement only, like AA guns or sniper fire at night.

 

[donmei]

Could triple based have slower burn characteristics?

The smaller a round it, generally the shorter its optimal barrel length, the faster powder it needs. The goal is to use only as fast a powder as is necessary to have nearly all the powder burn in the barrel.

A 9mm round uses faster powder than a .44 magnum round.
A rifle round, any rifle round (assault rifles use a round that is no different from any other rifle round) uses slower powder than most pistol rounds.

And it follows that big guns in tanks and naval vessels would use even slower powder than small arms.

So?? Is it simply that triple based powders burn slower?

 

[trurle]

Could triple based have slower burn characteristics?

The smaller a round it, generally the shorter its optimal barrel length, the faster powder it needs. The goal is to use only as fast a powder as is necessary to have nearly all the powder burn in the barrel.

A 9mm round uses faster powder than a .44 magnum round.
A rifle round, any rifle round (assault rifles use a round that is no different from any other rifle round) uses slower powder than most pistol rounds.

And it follows that big guns in tanks and naval vessels would use even slower powder than small arms.

So?? Is it simply that triple based powders burn slower?

Yes, adding 10% nitroguanidine in one example reduce burn speed by 50%. Will depend on other components though.
https://pubs.rsc.org/en/content/articlepdf/2017/ra/c7ra01607g
Also, it seems to be poorly compatible with cellulose-based smokeless powders
https://cameochemicals.noaa.gov/chemical/12105
and quite toxic (grade 3 toxicity)
From handling standpoint, nitroguanidine is as convenient to use as picric acid which was already phased out from military applications.