Hey guys! I was looking for information how different rifle powders have an effect on muzzle blast. I can find no real answers or calculators on the subject. I know, I must be real bored and can't afford a costly DB meter. What I was wondering is which powder would have more muzzle blast? 38.0 grains of IMR4198 or 38.0 grains of the slower IMR4895? Rifle would be a 308Win. with an 18inch barrel. Would the muzzle velocity come into play as far as muzzle blast also or is it more a matter of powder charge or both? I would appreciate any opinions or data on the matter. Stay safe and have a great 4th!
Effects of powder burn rate on muzzle blast
- Thread starter amtx2019
- Start date
I was always under the impression Quickload can give you an idea of this in the form of the % powder burned- ie, anything less than 100% would probably result in a noticable muzzle blast, or at least flash. But then again, I could also have missunderstood that.?
Well, yes and no- the main reason I always thought that was that it would most likely be impossible for any amount of powder to not actually burn, so the only thing that made sense to me was that the % unburnt was just to say , it burnt, but not where and when it matters- leaving outside the barrel as the obvious remaining place. At least for me...
QuickLoad can give you the actual distance the bullet travels at complete powder burn. In the lower right hand box (that shows chamber pressure and muzzle velocity) there is a line along the top that says something like click here for other info!
Reduced loads of H4895 would give less blast. You could load your .308 with 30-30 bullets and reduced loads and keep the velocity at or below 2500fps.
HODGDON® H4895® REDUCED RIFLE LOADS
https://imrpowder.com/wp-content/uploads/2016/11/h4895-reduced-rifle-loads.pdf
For Youth Hunting, Informal Target, and Plinking
Hodgdon Powder Company has found that H4895 can be loaded to reduced levels. H4895 was chosen because it is the slowest burning propellant that ignites uniformly in reduced charges. To create reduced loads, the 60% formula is recommended.
Find the H4895 load in the Reloading Data Center for your caliber and bullet.
Take the maximum H4895 charge listed and multiply by 60% (.6). The load may be adjusted up from there to achieve the desired velocity and accuracy.
This works only where H4895 is listed. DO NOT use in a cartridge where H4895 is not shown.
Example: 30-06 cartridge with 125 gr. Sierra SP bullet. Max load shown in the Reloading Data Center with H4895 is 53.7 grains. 53.7 X .6 = 32.2 grains. The shooter begins with this load, and may work up from there to obtain the desired velocity and accuracy for his reduced load.
HODGDON® H4895® REDUCED RIFLE LOADS
https://imrpowder.com/wp-content/uploads/2016/11/h4895-reduced-rifle-loads.pdf
For Youth Hunting, Informal Target, and Plinking
Hodgdon Powder Company has found that H4895 can be loaded to reduced levels. H4895 was chosen because it is the slowest burning propellant that ignites uniformly in reduced charges. To create reduced loads, the 60% formula is recommended.
Find the H4895 load in the Reloading Data Center for your caliber and bullet.
Take the maximum H4895 charge listed and multiply by 60% (.6). The load may be adjusted up from there to achieve the desired velocity and accuracy.
This works only where H4895 is listed. DO NOT use in a cartridge where H4895 is not shown.
Example: 30-06 cartridge with 125 gr. Sierra SP bullet. Max load shown in the Reloading Data Center with H4895 is 53.7 grains. 53.7 X .6 = 32.2 grains. The shooter begins with this load, and may work up from there to obtain the desired velocity and accuracy for his reduced load.
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It’s an interesting question, and I have no answers . I will say ball powders that I use 748 , H-335 “seem” to be louder then stick powders I use IMR 4064 , 4895 , 8208 .
I’ve also heard people say Longshot should be called loud shot .
I have no idea why this is and Im interested in the why .
I’ve also heard people say Longshot should be called loud shot .
I have no idea why this is and Im interested in the why .
Sounds like QuickLoad would hold some answers. If it provides a muzzle pressure I would say that would answer a lot of the question.I was interested in purchasing it until I decoded I needed more reloading components! lol...I have tried the H4895 for reduced loads Uncle Ed with some success. I have better accuracy with the IMR4198 and 125 to 135 grain bullets at around 2600 fps and cleaner burning. I agree Metal God. I have a good load with H322 but it seems noticeably louder than the IMR4198.
Ever considered going to a 300BO... .30 cal with just enough powder with no muzzle blast and ideal for shorter range (200 yards or less)
I certainly wouldn't advise substituting a faster powder at the same load weight.
I too shoot a couple of short tubed rifles for hunting and yes they are noisy beasts.
I like to pick one faster burn rate than you might use in a standard length rifle however I use the powder manufacturers tables to guide me and work up watching for pressure in the normal way.
A high % case fill is also something strived for so care must be taken when getting to higher velocities.
Faster powders are likely to increase throat erosion especially when pushed hard however for the short barreled hunting rifle that is generally not used for strings other than at the bench, throat erosion with powders more suitable to short tubes is something that should have little impact on the life of hunting barrel.
YMMV
I started hunting with the 300BO when it first came around Oso. I think it is a great round for 150 yards and under. I have taken a substantial number of deer and hogs with it. I still consider building a 300BO bolt rifle but I have so much 308 stuff it makes sense to stay with it. With a load of 36 grains of IMR4198 and a 125 grain Nosler BT I am getting about 2700 fps at the muzzle. Not as quiet as the 300 but very mild blast and recoil.
I understand what you are saying Homerange. 36.0 grains of the IMR4198 is my maximum load with a 125grain bullet. I am getting very good accuracy with the reduced case capacity and mild recoil witch is a benefit since I shoot of sticks and that helps keep eyes on target. I have wondered about throat erosion but figured with the lower charge and faster powder it would not be an issue.
Composition- look up the SDS safery data sheet for a powder. See what chemicals are used.
https://archives.fbi.gov/archives/a...ations/fsc/april2002/mccord.htm#disablemobile
The major classes of compounds in smokeless propellants include energetics, stabilizers, plasticizers, flash suppressants, deterrents, opacifiers, and dyes.
The blast and flash are caused by the combustion products of the gunpowder, and any remaining unburned powder, mixing with the ambient air.
https://archives.fbi.gov/archives/a...ations/fsc/april2002/mccord.htm#disablemobile
The major classes of compounds in smokeless propellants include energetics, stabilizers, plasticizers, flash suppressants, deterrents, opacifiers, and dyes.
The blast and flash are caused by the combustion products of the gunpowder, and any remaining unburned powder, mixing with the ambient air.
The manufacture of smokeless ball powder requires a more specialized procedure (National Research Council 1998). Nitrocellulose, stabilizers, and solvents are blended into a dough, then extruded through a pelletizing plate and formed into spheres. The solvent is removed from the granules, and nitroglycerine is impregnated into the granules. The spheres are then coated with deterrents and flattened with rollers. Finally, an additional coating with graphite and flash suppressants is applied , and the batch is mixed to ensure homogeneity.
While muzzle pressure is important, a big determinatorvof blast is the total gas volume. That is directly tied to the amount of powder burnt. A 30-06 blasts more than a 223 and a 300 magnum blasts more than a 30-06. But all get over shadowed by a 155 howitzer.
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