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A tale of 2 bullets...XTP and A-Frame in 41 magnum
Posted: Fri Oct 11, 2019 10:21 pm
by Ridgerunner665
These 2 bullets weigh the same... but the similarity ends there.
The Swift bullet is .726" long, the XTP is .673"... the nose of the bullet is shorter on the Swift, so it seats way deeper into the case.
The XTP seated to the front of the cannelure will have an overall length of around 1.585" (depending on case trim length)... the Swift seated to the front of the cannelure is 1.54", which is too short I think.
Looking at pictures of Federal ammo using the Swift bullet, they are crimped just over the bottom of the cannelure, which comes out to 1.565" overall length.
I have some test rounds loaded with the Swift bullets and 19, 19.5, 20, and 20.5 grains of Accurate 4100 to see what the speeds are over the chrono tomorrow... trying to find where the top end is.
Thats all I got for now... more to come tomorrow.
Re: A tale of 2 bullets...XTP and A-Frame in 41 magnum
Posted: Fri Oct 11, 2019 10:44 pm
by JEBar
looking forward to your coming reports
Re: A tale of 2 bullets...XTP and A-Frame in 41 magnum
Posted: Fri Oct 11, 2019 11:20 pm
by Mags
.
Looking forward to it.
Ridgerunner665 wrote: ↑Fri Oct 11, 2019 10:21 pm
... more to come tomorrow.
Re: A tale of 2 bullets...XTP and A-Frame in 41 magnum
Posted: Sat Oct 12, 2019 7:25 am
by GunnyGene
Ridgerunner665 wrote: ↑Fri Oct 11, 2019 10:21 pm
These 2 bullets weigh the same... but the similarity ends there.
The Swift bullet is .726" long, the XTP is .673"... the nose of the bullet is shorter on the Swift, so it seats way deeper into the case.
The XTP seated to the front of the cannelure will have an overall length of around 1.585" (depending on case trim length)... the Swift seated to the front of the cannelure is 1.54", which is too short I think.
Looking at pictures of Federal ammo using the Swift bullet, they are crimped just over the bottom of the cannelure, which comes out to 1.565" overall length.
I have some test rounds loaded with the Swift bullets and 19, 19.5, 20, and 20.5 grains of Accurate 4100 to see what the speeds are over the chrono tomorrow... trying to find where the top end is.
Thats all I got for now... more to come tomorrow.
Looking forward to this, since we have the same model rifle.
Re: A tale of 2 bullets...XTP and A-Frame in 41 magnum
Posted: Sat Oct 12, 2019 10:57 am
by Ridgerunner665
OK... first things first when I don't have specific load data to work with.
Calibrate QuickLoad to the Henry.... fired one of my steel banging loads through the rifle then measured its expanded capacity using water... QL's default for the 41 Magnum is 35.5 grains, the measured capacity of my Henry BBSC is 36.8 grains.
Calibrate QuickLoad to the bullets... the default bullet length for the Swift bullet is .730", actual measured length of my batch is .726".
The default for the Hornady bullet is .617", actual measured length of my batch is .673".
Re: A tale of 2 bullets...XTP and A-Frame in 41 magnum
Posted: Sat Oct 12, 2019 11:31 am
by Ridgerunner665
This is the Swift bullet with Accurate 4100 powder
19 grains....QL predicted 1,631 fps...MagnetoSpeed says 1,615 fps.
19.5 grains...QL predicted 1,672 fps...MagnetoSpeed says 1,670 fps.
20 grains....QL predicted 1,714 fps...MagnetoSpeed says 1,678 fps.
20.5 grains...QL predicted 1,755 fps...MagnetoSpeed says 1,716 fps.
I'm thinking 20 or 20.5 grains is gonna be max for Accurate 4100 and the 210 grain Swift A-Frame... gonna load 5 each and see what the averages look like.
Be back in a bit.
Re: A tale of 2 bullets...XTP and A-Frame in 41 magnum
Posted: Sat Oct 12, 2019 2:23 pm
by Ridgerunner665
Looks like 20.3 grains of 4100 is maxed out with the 210 Swift...
1,705 fps 10 shot average... best I can figure this is running around 35,300 psi, but I don't have pressure equipment to test for sure so that is nothing more than a SWAG.
SAAMI says 36,000 psi maximum average pressure, 37,100 psi maximum probable lot average (maximum for a specific lot of ammo), and 38,800 psi maximum probable sample average (max for any given round in a lot).
Stopping at 35,300 psi seems a reasonable safe limit...Accurate powders load data for this powder also stops in that range.
Re: A tale of 2 bullets...XTP and A-Frame in 41 magnum
Posted: Sat Oct 12, 2019 2:28 pm
by GunnyGene
Ridgerunner665 wrote: ↑Sat Oct 12, 2019 2:23 pm
Looks like 20.3 grains of 4100 is maxed out with the 210 Swift...
1,705 fps 10 shot average... best I can figure this is running around 35,300 psi, but I don't have pressure equipment to test for sure so that is nothing more than a SWAG.
I'd call that acceptable although a little on the low side compared to the Underwood XTP I chrono'd a couple weeks ago (1738 avg). What was the spread?
Re: A tale of 2 bullets...XTP and A-Frame in 41 magnum
Posted: Sat Oct 12, 2019 2:30 pm
by Ridgerunner665
See the edit above... the Swift is a longer bullet, smaller combustion chamber (usable case capacity), smaller powder charge for the same pressure... all adds up to a little lower velocity.
ES was 30, SD was 12.
Re: A tale of 2 bullets...XTP and A-Frame in 41 magnum
Posted: Sat Oct 12, 2019 2:34 pm
by Ridgerunner665
I'm going to shoot a string with my XTP load now... haven't shot a string using the MagnetoSpeed with that load... curious to see how fast the MagnetoSpeed says it is.
The optical chrono (Caldwell) said 1,725 fps...