amount of powder ?

rebs · September 4, 2012, 12:35 PM

Loading for a 223 AR15.
If a load of 24.5 of H335 powder gives you excellent accuracy with a 55 gr fmjbt wouldn't that same amount of powder be very accurate for say a 55 gr hpbt or a flat base hollow point bullet being fired in the same rifle ?
Or do different bullets being the same weight need a different powder charge ?

Goatwhiskers · September 4, 2012, 12:43 PM

Maybe, or then maybe not. You need to experiment and find out what "your" gun likes. Why may there be differences? Durned if I know, but that's the fun of reloading. GW

math teacher · September 4, 2012, 07:26 PM

Bullets vary in hardness, bearing surface, shape and other variables. Any time you change any component, it can make a difference.

Marco Califo · September 4, 2012, 10:40 PM

Sierra says yes. They list 7 different bullets above ONE load table, applicable to all. I even use their data with other brands of bullets, if the weight is the same.
http://thefiringline.com/forums/atta...3&d=1326064897

NWPilgrim · September 4, 2012, 11:47 PM

The OP asked about different bullets having the same accuracy, not if the powder charge is safe for all. Accuracy may change from one bullet style to another. Worth testing to be sure.

rebs · September 5, 2012, 07:16 AM

Yes that is what I was asking. Is accuracy the same with bullets of the same weight, but different designs using the same powder charge.
Example a 55 gr fmjhp is most accurate with 24.5 gr of H335 in my rifle. So would the same amount of powder be the accuracy load for different types of bullets in the same weight, such as a hollow point, soft point etc..

jmr40 · September 5, 2012, 09:09 AM

Anytime you change something accuracy, pressure, and velocity could change. A 55 gr bullet from company "A" may have more surface in contact with the barrel than the same weight bullet from company "B" resulting in more pressure and velocity. This may or may not effect accuracy.

Same when you change brass, primers, or even the same powder from a different can.

tobnpr · September 5, 2012, 08:42 PM

Yep...the load should be safe, unless you're pushing towards the hot end.
Loads are based on weight, so when you can't find load info for a particular bullet, take the data from a similar (hopefully exact) weight bullet, and start low and work up like usual.

Accuracy is whole 'nother animal.
Bullet shape- ogive- and length, even for the same weight bullet, can vary a LOT.

We'd had good success with 6.5, 123 grain Amax's in our 6.5 Grendel AR. We'd also had good results with Nosler's Custom Competition bullets in .223, so when I saw they had a 6.5 in 123 grain, I bought a box...

Didn't shoot nearly as well as the Amax's, but more importantly to note is that they have a completely different ogive- like a SMK- and the loaded length to the ogive was much less than the Amax.

September 4, 2012, 12:35 PM	#1
rebs Senior Member Join Date: January 10, 2012 Posts: 3,881	amount of powder ? Loading for a 223 AR15. If a load of 24.5 of H335 powder gives you excellent accuracy with a 55 gr fmjbt wouldn't that same amount of powder be very accurate for say a 55 gr hpbt or a flat base hollow point bullet being fired in the same rifle ? Or do different bullets being the same weight need a different powder charge ?

September 4, 2012, 10:40 PM	#4
Marco Califo Senior Member Join Date: April 4, 2011 Location: LA (Greater Los Angeles Area) Posts: 2,600	Sierra says yes. Sierra says yes. They list 7 different bullets above ONE load table, applicable to all. I even use their data with other brands of bullets, if the weight is the same. http://thefiringline.com/forums/atta...3&d=1326064897 __________________ ............

September 4, 2012, 12:43 PM	#2
Goatwhiskers Senior Member Join Date: April 8, 2009 Location: Batchelor, La. Posts: 579	Maybe, or then maybe not. You need to experiment and find out what "your" gun likes. Why may there be differences? Durned if I know, but that's the fun of reloading. GW

September 4, 2012, 07:26 PM	#3
math teacher Senior Member Join Date: February 5, 2012 Location: Southwest WA Coast Posts: 559	Bullets vary in hardness, bearing surface, shape and other variables. Any time you change any component, it can make a difference.

September 4, 2012, 11:47 PM	#5
NWPilgrim Senior Member Join Date: September 29, 2008 Location: Oregon Posts: 2,346	The OP asked about different bullets having the same accuracy, not if the powder charge is safe for all. Accuracy may change from one bullet style to another. Worth testing to be sure.

September 5, 2012, 07:16 AM	#6
rebs Senior Member Join Date: January 10, 2012 Posts: 3,881	Yes that is what I was asking. Is accuracy the same with bullets of the same weight, but different designs using the same powder charge. Example a 55 gr fmjhp is most accurate with 24.5 gr of H335 in my rifle. So would the same amount of powder be the accuracy load for different types of bullets in the same weight, such as a hollow point, soft point etc..

September 5, 2012, 09:09 AM	#7
jmr40 Senior Member Join Date: June 15, 2008 Location: Georgia Posts: 10,809	Anytime you change something accuracy, pressure, and velocity could change. A 55 gr bullet from company "A" may have more surface in contact with the barrel than the same weight bullet from company "B" resulting in more pressure and velocity. This may or may not effect accuracy. Same when you change brass, primers, or even the same powder from a different can.

September 5, 2012, 08:42 PM	#8
tobnpr Senior Member Join Date: August 1, 2010 Location: Tampa Bay Posts: 4,556	Yep...the load should be safe, unless you're pushing towards the hot end. Loads are based on weight, so when you can't find load info for a particular bullet, take the data from a similar (hopefully exact) weight bullet, and start low and work up like usual. Accuracy is whole 'nother animal. Bullet shape- ogive- and length, even for the same weight bullet, can vary a LOT. We'd had good success with 6.5, 123 grain Amax's in our 6.5 Grendel AR. We'd also had good results with Nosler's Custom Competition bullets in .223, so when I saw they had a 6.5 in 123 grain, I bought a box... Didn't shoot nearly as well as the Amax's, but more importantly to note is that they have a completely different ogive- like a SMK- and the loaded length to the ogive was much less than the Amax.