jwin
Button Buck
Posts: 14
|
Post by jwin on Mar 1, 2011 12:40:49 GMT -5
Would it be ok to ask a favor? If you have time, could you plug in some numbers into Quickload. I am using Sr 4759 and 200 gr XTP with Harv light blue sabot. My barrel is 24" overall with about a 2" breechplug. I have shot up to 40grs of 4759. Am trying to find where is the upper limit of this powder in grs. Wondering about pressure and velocity. Thanks if you get time. James
|
|
jwin
Button Buck
Posts: 14
|
Post by jwin on Mar 1, 2011 13:09:29 GMT -5
Got to thinking later, I should have put this in a pm. Sorry
|
|
|
|
Post by rangeball on Mar 1, 2011 13:10:39 GMT -5
Would it be ok to ask a favor? If you have time, could you plug in some numbers into Quickload. I am using Sr 4759 and 200 gr XTP with Harv light blue sabot. My barrel is 24" overall with about a 2" breechplug. I have shot up to 40grs of 4759. Am trying to find where is the upper limit of this powder in grs. Wondering about pressure and velocity. Thanks if you get time. James Most likely you're sabot will tell you the upper limit of powder. |
|
|
|
Post by edge on Mar 1, 2011 14:05:41 GMT -5
I assume that you are using a 45 caliber rifle correct?
Unfortunately my version of QL does NOT have 4759.
IMR powder selector shows that 4759 has a rating of 210
If I use the Powley computer I find that 45 grains of 4759 should get you 2514 fps @ 34.7 kpsi with a powder selector rating of 203
Powley GENERALLY over estimates pressure in large straight bores so I would be very confident in this load as far as safety.
Were I to substitute N110 then QL would estimate the 45 grain load at 2702 fps @ 41.9 kpsi and 99% burnt.
Since 45 grains of 4759 takes up 69 grains of water capacity and N110 only takes up 57.6 grains of water the pressure should be much lower for 4759 than the N110.
Will you be able to shoot 45 grains without blowing the sabot is another issue. Personally I would not be afraid of 50 grains but I doubt you will even get close to that with 4759.
edge.
SR4759 210
IMR-4227 180
IMR-4198 160
IMR-3031 135
IMR-4064 120
IMR-4895 115
IMR-4320 110
IMR-4350 100
IMR-4831 95
|
|
jwin
Button Buck
Posts: 14
|
Post by jwin on Mar 1, 2011 16:03:27 GMT -5
Thank you very much sir. James
|
|
|
|
Post by Richard on Mar 2, 2011 15:01:02 GMT -5
jwin.............If you check my posts on Jan. 24 and Feb. 9, you will see information and targets using SR4759. To recap........... 195 Barnes with 54 gr. of SR4759 gave me an average of 2869 fps out of a 26" PN .45. It had decent ES of 27 fps for five shots with a 1.7" three shot group. 200 XTP with 50 gr. of SR4759 gave an average of 2737 fps with a low 21 fps ES and four shots in .9" I exclusively use only the Harvester smooth blue sabots. I did experience a blown sabot with the Barnes bullet but believe it was due to me not cooling the barrel. I rushed it and did not put the cool rod in  It appears to be an excellent single powder load. Richard |
|
jwin
Button Buck
Posts: 14
|
Post by jwin on Mar 3, 2011 6:31:33 GMT -5
Thanks Richard, James
|
|
|
|
Post by cuda on Mar 3, 2011 13:13:47 GMT -5
Edge on you list of powders sr4759 is 210 and the imr4198 is 160. So is the imr4198 less or more pressure? I am using 69gr of imr4198 and a 300gr Rem BCR in my 50.
|
|
|
|
Post by edge on Mar 3, 2011 13:38:53 GMT -5
Edge on you list of powders sr4759 is 210 and the imr4198 is 160. So is the imr4198 less or more pressure? I am using 69gr of imr4198 and a 300gr Rem BCR in my 50. These are the relative burn rates of IMR powders. Using my Powley calculator your load suggests a powder with a burn rate of 168 which is between 4227 and 4198. If you chose 4227 the pressure would be higher and lower with 4198 My calculator estimates that your load would yield about 2536 fps @ 44 kpsi WITH THIS CAVEAT: A comparison was made between pressures calculated by this method, and pressures measured for the same loads as recorded in the DuPont handloader's guide for Smokeless Powders (1975-1976). The results indicated that the calculated pressure for cartridges from about .25-caliber to .338-caliber were usually within about 10% of the measured pressures, about equally divided above and below. For the smaller calibers, the calculated pressures were typically somewhat below the measured pressures, the average being about 4% lower for the 6mm/.243 calibers, and about 8% for the .22 calibers. For calibers larger than the .338, the calculated pressures were typically somewhat higher than the measured pressures, the average being about 7% higher for the .35-caliber cartridges, and about 15% higher for the .458 Winchester Magnum. The .375 H&H Magnum, is the exception to the trend, gave calculated pressures in very good agreement with the measured pressures. SR4759 210 IMR-4227 180 IMR-4198 160 IMR-3031 135 IMR-4064 120 IMR-4895 115 IMR-4320 110 IMR-4350 100 IMR-4831 95 edge. |
|
It appears to be an excellent single powder load. 