roachcreek
09-15-2013, 02:36 PM
I recently bought two vintage molds off of Ebay, a 257464 and a Herters 25/100 that I assumed was the same as the Ideal 257418. It turned out that the Herters mold was not a 257418 nor was it even a 100 grain bullet. Cast from 20-1 it weighs within + or_ .4 grains of the 257464 or at around 94 grains.
Which brought up something I have been wanting to do for some time, which was to test the trajectory of the same weight bullets at the same velocity to see how close Handloads.com came to predicting the trajectory difference.
I shoot a Haley 257 Scandalous PCP air rifle which is tethered to a 66 cf Firemans' bottle and regulated to 3600 PSI. Both bullets from this rifle gave the same velocity of 1010FPS + or- 5 FPS, it is very consistent.
http://i1022.photobucket.com/albums/af343/chbartlemay/CIMG2443_zpsc816c482.jpg (http://s1022.photobucket.com/user/chbartlemay/media/CIMG2443_zpsc816c482.jpg.html)
Handloads.com said that the Herters 25/100 spitzer would be 10.25 inches higher than the round nosed 257464 bullet if the velocity was the same and the weight was the same.
So I shot 4 5 shot groups in a 3 MPH wind, holding for the wind, which is difficult here as the wind swirls in the 11 acre vineyard surrounded by mature Douglas fir trees and setting on the east side of the piedmont on Oregon coast range. Handolads.com gives a wind drift of 3.72 inches for the 25/100 and 6 inches for the 257464.
Both bullets start out at 213 FPE and the 257464 has 137 FPE remaining at 300 yards while the 25/100 has 161 FPE left. Perhaps a mute point due to the fact that neither bullet is designed to give energy transferal.
I had zeroed and checked for drop on the center plate and while shooting the two different bullets. I found that with a zero on the 25/100, I needed a correction of 3 MOA on the 4.5x14 30 MM SF Leupold VX111's MOA Holland reticle at 300 yards. This was 9.1 inches and a little better than what Handloads.com said it would be but very close considering it is 300 yards and I have a mid range trajectory of 50 inches.
View through the Leupold with the Holland reticle, using a zero with the 25/100 bullet, I held on the 3 MOA dot to hit with the Ideal 257464.
http://i1022.photobucket.com/albums/af343/chbartlemay/CIMG2450_zpsb1220cfe.jpg (http://s1022.photobucket.com/user/chbartlemay/media/CIMG2450_zpsb1220cfe.jpg.html)
Both bullets shot similar groups, hovering around 1.2 MOA in the wind, which I did not think was too bad, although after shooting the first 3 257464 bullets into 1.5 inches during the first 5 shot group I wish the wind had been still to really see what the bullets would do.
The 25/100 posted the best group of 3.6 inches or 1.16 MOA which is not bad for non weight sorted bullets and the first bullets from a new mold. I usually sort to + or_ one tenth on this rifle and it regularly shoots sub moa on windless days.
I was using the 1-10 twist 36 inch TJ barrel which is part of the two scope, two barrel set this rifle is comprised of and lubing with Silicone oil and Imperial sizing wax which was not removed after sizing.
The target and the 4 groups after sight in shots were painted over
http://i1022.photobucket.com/albums/af343/chbartlemay/CIMG2451_zpsa1a2f97c.jpg (http://s1022.photobucket.com/user/chbartlemay/media/CIMG2451_zpsa1a2f97c.jpg.html)
Best 25/100 group
http://i1022.photobucket.com/albums/af343/chbartlemay/CIMG2452_zps0075662f.jpg (http://s1022.photobucket.com/user/chbartlemay/media/CIMG2452_zps0075662f.jpg.html)
Best 257464 group
http://i1022.photobucket.com/albums/af343/chbartlemay/CIMG2454_zpsd2e2e2ff.jpg (http://s1022.photobucket.com/user/chbartlemay/media/CIMG2454_zpsd2e2e2ff.jpg.html)
The Haley 257 Scandalous ready to go
http://i1022.photobucket.com/albums/af343/chbartlemay/CIMG2444_zps921e7efc.jpg (http://s1022.photobucket.com/user/chbartlemay/media/CIMG2444_zps921e7efc.jpg.html)
Which brought up something I have been wanting to do for some time, which was to test the trajectory of the same weight bullets at the same velocity to see how close Handloads.com came to predicting the trajectory difference.
I shoot a Haley 257 Scandalous PCP air rifle which is tethered to a 66 cf Firemans' bottle and regulated to 3600 PSI. Both bullets from this rifle gave the same velocity of 1010FPS + or- 5 FPS, it is very consistent.
http://i1022.photobucket.com/albums/af343/chbartlemay/CIMG2443_zpsc816c482.jpg (http://s1022.photobucket.com/user/chbartlemay/media/CIMG2443_zpsc816c482.jpg.html)
Handloads.com said that the Herters 25/100 spitzer would be 10.25 inches higher than the round nosed 257464 bullet if the velocity was the same and the weight was the same.
So I shot 4 5 shot groups in a 3 MPH wind, holding for the wind, which is difficult here as the wind swirls in the 11 acre vineyard surrounded by mature Douglas fir trees and setting on the east side of the piedmont on Oregon coast range. Handolads.com gives a wind drift of 3.72 inches for the 25/100 and 6 inches for the 257464.
Both bullets start out at 213 FPE and the 257464 has 137 FPE remaining at 300 yards while the 25/100 has 161 FPE left. Perhaps a mute point due to the fact that neither bullet is designed to give energy transferal.
I had zeroed and checked for drop on the center plate and while shooting the two different bullets. I found that with a zero on the 25/100, I needed a correction of 3 MOA on the 4.5x14 30 MM SF Leupold VX111's MOA Holland reticle at 300 yards. This was 9.1 inches and a little better than what Handloads.com said it would be but very close considering it is 300 yards and I have a mid range trajectory of 50 inches.
View through the Leupold with the Holland reticle, using a zero with the 25/100 bullet, I held on the 3 MOA dot to hit with the Ideal 257464.
http://i1022.photobucket.com/albums/af343/chbartlemay/CIMG2450_zpsb1220cfe.jpg (http://s1022.photobucket.com/user/chbartlemay/media/CIMG2450_zpsb1220cfe.jpg.html)
Both bullets shot similar groups, hovering around 1.2 MOA in the wind, which I did not think was too bad, although after shooting the first 3 257464 bullets into 1.5 inches during the first 5 shot group I wish the wind had been still to really see what the bullets would do.
The 25/100 posted the best group of 3.6 inches or 1.16 MOA which is not bad for non weight sorted bullets and the first bullets from a new mold. I usually sort to + or_ one tenth on this rifle and it regularly shoots sub moa on windless days.
I was using the 1-10 twist 36 inch TJ barrel which is part of the two scope, two barrel set this rifle is comprised of and lubing with Silicone oil and Imperial sizing wax which was not removed after sizing.
The target and the 4 groups after sight in shots were painted over
http://i1022.photobucket.com/albums/af343/chbartlemay/CIMG2451_zpsa1a2f97c.jpg (http://s1022.photobucket.com/user/chbartlemay/media/CIMG2451_zpsa1a2f97c.jpg.html)
Best 25/100 group
http://i1022.photobucket.com/albums/af343/chbartlemay/CIMG2452_zps0075662f.jpg (http://s1022.photobucket.com/user/chbartlemay/media/CIMG2452_zps0075662f.jpg.html)
Best 257464 group
http://i1022.photobucket.com/albums/af343/chbartlemay/CIMG2454_zpsd2e2e2ff.jpg (http://s1022.photobucket.com/user/chbartlemay/media/CIMG2454_zpsd2e2e2ff.jpg.html)
The Haley 257 Scandalous ready to go
http://i1022.photobucket.com/albums/af343/chbartlemay/CIMG2444_zps921e7efc.jpg (http://s1022.photobucket.com/user/chbartlemay/media/CIMG2444_zps921e7efc.jpg.html)