Expander diameter vs. crimp - a question
+5
noylj
243winxb
davekp
Wobbley
Aprilian
9 posters
Page 1 of 2
Page 1 of 2 • 1, 2
Expander diameter vs. crimp - a question
Over on FB, KC made a post about his custom expander for CF that he made in order to not have the case resize the WC bullets. I wondered if that applied to .45 and so took measurements of my two expanders - which are .450 and .451 (Redding and Lyman M, respectively). I loaded and pulled various bullets and the .451 is fine for hard cast but for swaged, I was sizing the bullets by one thousandth diameter. Another post on that conversation was linked to Noe Bullets' larger expander mandrels so I ordered a few in the larger sizes to play with for the swaged bullets I already own. Those swaged bullets are on the shelf because they were inaccurate (and I now think I know part of the reason).
If I understand correctly, crimp and case mouth tension together are what stops setback and controls the pressure at which the bullet releases (both impacting accuracy). The swaged bullets (pre-crimping) came out with one hammer blow vs. the hard cast taking 4-5 to dislodge the bullet. If the case mouth tension is less (because of both the wider expansion and the softer bullet) do I need to crimp swaged more than my current .469" for hard cast?
Thanks in advance.
If I understand correctly, crimp and case mouth tension together are what stops setback and controls the pressure at which the bullet releases (both impacting accuracy). The swaged bullets (pre-crimping) came out with one hammer blow vs. the hard cast taking 4-5 to dislodge the bullet. If the case mouth tension is less (because of both the wider expansion and the softer bullet) do I need to crimp swaged more than my current .469" for hard cast?
Thanks in advance.
Last edited by Aprilian on Thu Jul 13, 2017 4:27 pm; edited 1 time in total
Aprilian- Posts : 987
Join date : 2016-05-13
Location : Minnesota
Re: Expander diameter vs. crimp - a question
There was one older gunsmith that advocated crimping to .463. That was probably with relatively soft bullets of the 1960s as most shooters were using lead with wheelweights and a touch of tin if they needed it.
Wobbley- Admin
- Posts : 4715
Join date : 2015-02-13
Re: Expander diameter vs. crimp - a question
If you are sizing swaged with the .451 expander, what diameter are the bullets before loading? Seems like a .451 sized case couldn't swage a bullet .001 more.
What are the diameter of your cast bullets before loading?
.469 crimp might be excessive.
What are the diameter of your cast bullets before loading?
.469 crimp might be excessive.
davekp- Posts : 315
Join date : 2011-06-11
Re: Expander diameter vs. crimp - a question
Dave, I'll have to check my detailed notes later, but I believe the swaged measured at .4525" consistently (test of 4 Magnus 814s). My cases are mixed, I think I grabbed all Winchester for this experiment, but did not record that on my notes. All of the bullets took the same amount of (or less) force to seat as my hard cast. You mention the expander diameter, I should have measured the interior case diameter as brass has elastic deformation characteristics and will bounce back some. Without that elastic deformation, we'd never get the spent cases back out of the chamber. Another way of explaining that property is that the expander will not just drop into the case after expanding it in the press.
Why do you say that .469 is excessive? What has your experimenting on accuracy and crimp shown you? I measure crimp by setting the calipers jaws so they just start over the mouth to confirm crimp diameter. Is that the same way you measure yours?
Thanks
Why do you say that .469 is excessive? What has your experimenting on accuracy and crimp shown you? I measure crimp by setting the calipers jaws so they just start over the mouth to confirm crimp diameter. Is that the same way you measure yours?
Thanks
Aprilian- Posts : 987
Join date : 2016-05-13
Location : Minnesota
Re: Expander diameter vs. crimp - a question
To much taper crimp may size the bullet smaller and make the bullet have less neck tension.
Same as a Lee factory crimp die may size a bullet smaller in the cartridge.
Try measuring the FL sized case , middle of bullet area, before and after seating a bullet. My cast expands the case .002" on seating of the bullet. Producing about 40 lbs to move the bullets.
Less neck tension may be better for soft swagged, but from another post, not all swagged are soft.
[url=https://s338.photobucket.com/user/joe1944usa/media/2015 Reloading/45acp NeckTension A_zps2nhf4njc.jpg.html]Link to Photobucket. Spam blocker needed.[/url]
https://s338.photobucket.com/user/joe1944usa/media/2015%20Reloading/45acp%20NeckTension%20A_zps2nhf4njc.jpg.html
Same as a Lee factory crimp die may size a bullet smaller in the cartridge.
Try measuring the FL sized case , middle of bullet area, before and after seating a bullet. My cast expands the case .002" on seating of the bullet. Producing about 40 lbs to move the bullets.
Less neck tension may be better for soft swagged, but from another post, not all swagged are soft.
[url=https://s338.photobucket.com/user/joe1944usa/media/2015 Reloading/45acp NeckTension A_zps2nhf4njc.jpg.html]Link to Photobucket. Spam blocker needed.[/url]
https://s338.photobucket.com/user/joe1944usa/media/2015%20Reloading/45acp%20NeckTension%20A_zps2nhf4njc.jpg.html
243winxb- Posts : 332
Join date : 2013-12-02
Age : 79
Location : USA
Re: Expander diameter vs. crimp - a question
OP said " My cases are mixed "
Not good. Waste of time to fine tune an expander.
Not good. Waste of time to fine tune an expander.
Last edited by 243winxb on Wed Jul 19, 2017 5:23 pm; edited 2 times in total (Reason for editing : Made a quote from OP Fixed my spelling.)
243winxb- Posts : 332
Join date : 2013-12-02
Age : 79
Location : USA
Re: Expander diameter vs. crimp - a question
Thanks, the swaged bullets I have must be soft to change diameter on seating. I will try that case measurement in a few days.
If I understand your comment, too much crimp alters the case below the crimp, thereby causing the section below the crimp to get wider. Since we are not displacing case material in crimping (therefore the case thickness is the same) that wider section indicates that the tension on the bullet - at that wider spot - is less. Is that what you meant?
If I set my caliper jaws parallel to the case to give me a visual whether I had widened the case below the crimp, would parallel case sides indicate I had not reduced tension?
How did you measure the 40# to move the bullet?
Sadly, that photo is being blocked by Photobucket.
If I understand your comment, too much crimp alters the case below the crimp, thereby causing the section below the crimp to get wider. Since we are not displacing case material in crimping (therefore the case thickness is the same) that wider section indicates that the tension on the bullet - at that wider spot - is less. Is that what you meant?
If I set my caliper jaws parallel to the case to give me a visual whether I had widened the case below the crimp, would parallel case sides indicate I had not reduced tension?
How did you measure the 40# to move the bullet?
Sadly, that photo is being blocked by Photobucket.
Aprilian- Posts : 987
Join date : 2016-05-13
Location : Minnesota
Re: Expander diameter vs. crimp - a question
![Expander diameter vs. crimp - a question 45acpn10](https://i.servimg.com/u/f11/18/92/60/96/45acpn10.jpg)
I check neck tension by loading a dummy round. Then push against a bath room scale with a lever to slowly apply pressure. Not high tech testing, but you can tell the difference between 40 lbs to over 100 where the bullet doesn't even move.
My test was without adjusting any of the 4 dies, as they are set just perfect for my Starline Brass. Using my old Dillion RL-450 progressive.
Hope this helps.
243winxb- Posts : 332
Join date : 2013-12-02
Age : 79
Location : USA
Re: Expander diameter vs. crimp - a question
See the BHN or hardness of swaged vs cast. A good all around is 15 bhn.
I have been casting for about 40 years.
https://www.bullseyeforum.net/t7834-swaged-bullets
I have been casting for about 40 years.
https://www.bullseyeforum.net/t7834-swaged-bullets
243winxb- Posts : 332
Join date : 2013-12-02
Age : 79
Location : USA
Re: Expander diameter vs. crimp - a question
No. Sorry i don't explain well.Aprilian wrote:If I understand your comment, too much crimp alters the case below the crimp, thereby causing the section below the crimp to get wider. Since we are not displacing case material in crimping (therefore the case thickness is the same) that wider section indicates that the tension on the bullet - at that wider spot - is less. Is that what you meant?
If you taper crimp a loaded round to much, with some taper crimp dies, this happens.
Both lead bullet and brass are compressed. On spring back of both, lead will spring back very little or not at all.
Brass will spring back a lot more than lead.
We know from Corbin's swaging website info, that a jacketed bullet sized down more than .005" will leave a lead core loose inside the rifle bullets jacket. Remember, brass springs back more than lead.
There will be no outward appearance of a deformed cartridge, but the bullet diameter may have been made smaller in diameter. More so with soft lead bullets.
243winxb- Posts : 332
Join date : 2013-12-02
Age : 79
Location : USA
Re: Expander diameter vs. crimp - a question
That's great info, thanks.
I hadn't thought about the lower rebound of the lead vs. the brass - one more variable to understand. I like how you measure neck tension and can tie it directly to the force required to dislodge the bullet. I'm assuming the reason you did that full test is that you equate higher neck tension to higher accuracy. Is that a generally understood concept?
I'm lucky that my test was before crimping, so my reduction of the diameter was not related to the crimp (this time). I'll fix the seating reduction first and then test the impact of crimping. Once I crimp a test round and want to pull the bullet - to remeasure for reduction in diameter, how do I do that? Wouldn't an inertia hammer squeeze the bullet through the case mouth (as there is no powder burn to open the case mouth and release the bullet) and reduce the rear driving bands which were not impacted by the taper crimp? Does one need to dremel the side of the case to release the radial pressure on the crimped case and bullet?
I hadn't thought about the lower rebound of the lead vs. the brass - one more variable to understand. I like how you measure neck tension and can tie it directly to the force required to dislodge the bullet. I'm assuming the reason you did that full test is that you equate higher neck tension to higher accuracy. Is that a generally understood concept?
I'm lucky that my test was before crimping, so my reduction of the diameter was not related to the crimp (this time). I'll fix the seating reduction first and then test the impact of crimping. Once I crimp a test round and want to pull the bullet - to remeasure for reduction in diameter, how do I do that? Wouldn't an inertia hammer squeeze the bullet through the case mouth (as there is no powder burn to open the case mouth and release the bullet) and reduce the rear driving bands which were not impacted by the taper crimp? Does one need to dremel the side of the case to release the radial pressure on the crimped case and bullet?
Aprilian- Posts : 987
Join date : 2016-05-13
Location : Minnesota
Re: Expander diameter vs. crimp - a question
Looks like you have a lot of testing to do. I use cast bullets.
Have fun. Good luck.
Have fun. Good luck.
243winxb- Posts : 332
Join date : 2013-12-02
Age : 79
Location : USA
Re: Expander diameter vs. crimp - a question
I determined the expander diameter by simply measuring the case ID before and after expansion. My goal was to have the case ID 0.001-0.002" smaller than actual bullet diameter.
So, being lazy, I would take a case ID that was 0.448", use a 0.450" expander, and find that the case ID is now 0.449". So, if I want 0.4505" ID, then I order a 0.4515" expander. So far, it has worked well.
I found that under-expanding would make seating straight more difficult (had more case with the "bullet-base case bulge) and lead bullets were sometimes swaged down. Getting the right expander minimizes both.Getting the right sized Lyman M-die does even more for eliminating the problems.
So, being lazy, I would take a case ID that was 0.448", use a 0.450" expander, and find that the case ID is now 0.449". So, if I want 0.4505" ID, then I order a 0.4515" expander. So far, it has worked well.
I found that under-expanding would make seating straight more difficult (had more case with the "bullet-base case bulge) and lead bullets were sometimes swaged down. Getting the right expander minimizes both.Getting the right sized Lyman M-die does even more for eliminating the problems.
noylj- Posts : 426
Join date : 2012-03-10
Age : 74
Location : SW USA
Re: Expander diameter vs. crimp - a question
Today I took a stab at testing what works with Magnus 814 185 gr. SWCHP using Noe Bullets' .451, .452 and .452 expanders.243winxb wrote:Looks like you have a lot of testing to do.
Conclusions:
.452 and .453 leave wide section below mouth which is not reduced with my Lyman crimp die
.452 and .453 bullets are too loose (post crimp) and did not resist my push test
.451 is a good sizer and only reduces swaged bullet diameter to .451 after removing with impact hammer
Magnus 814 swaged SWCHP (.452) | measured as | 0.4530 | |
Winchester multiple fired cases | |||
Redding dual ring sizer | |||
Redding seating die - setting 20 | |||
Lyman crimping die | |||
RCBS dial calipers (tested with guage blocks) | |||
Crimp | 0.4695 | ||
Noe bullets expander | 0.4510 | 0.4520 | 0.4530 |
OD below flair | 0.4695 | 0.4710 | 0.4720 |
OD at mouth flair | 0.4735 | 0.4755 | 0.4770 |
bullet location to lube band by hand placement | below | middle | above |
COAL | 1.2240 | 1.2210 | 1.2190 |
case OD over bullet | 0.4715 | 0.4725 | 0.4730 |
case OD at flair (widest point) | 0.4720 | 0.4730 | 0.4735 |
push test | resisted | fail | fail |
Bullet after | 0.4510 | 0.4515 | 0.4520 |
# of hits to dislodge bullet (not an accurate test) | 2.25 | 3 | 2 |
Aprilian- Posts : 987
Join date : 2016-05-13
Location : Minnesota
Re: Expander diameter vs. crimp - a question
how far into the case does the expander expand?Aprilian wrote:Today I took a stab at testing what works with Magnus 814 185 gr. SWCHP using Noe Bullets' .451, .452 and .452 expanders.243winxb wrote:Looks like you have a lot of testing to do.
Conclusions:
.452 and .453 leave wide section below mouth which is not reduced with my Lyman crimp die
.452 and .453 bullets are too loose (post crimp) and did not resist my push test
.451 is a good sizer and only reduces swaged bullet diameter to .451 after removing with impact hammer
Magnus 814 swaged SWCHP (.452) measured as 0.4530 Winchester multiple fired cases Redding dual ring sizer Redding seating die - setting 20 Lyman crimping die RCBS dial calipers (tested with guage blocks) Crimp 0.4695 Noe bullets expander 0.4510 0.4520 0.4530 OD below flair 0.4695 0.4710 0.4720 OD at mouth flair 0.4735 0.4755 0.4770 bullet location to lube band by hand placement below middle above COAL 1.2240 1.2210 1.2190 case OD over bullet 0.4715 0.4725 0.4730 case OD at flair (widest point) 0.4720 0.4730 0.4735 push test resisted fail fail Bullet after 0.4510 0.4515 0.4520 # of hits to dislodge bullet (not an accurate test) 2.25 3 2
Chris Miceli- Posts : 2715
Join date : 2015-10-27
Location : Northern Virginia
Re: Expander diameter vs. crimp - a question
Chris, as the expanders are rounded on the bottom, how would I accurately measure the depth it goes into the case?
Aprilian- Posts : 987
Join date : 2016-05-13
Location : Minnesota
Re: Expander diameter vs. crimp - a question
By only measuring the straight sidewall of the expander.
Watch it as you feed a case up and mark the expander with a fineline sharpie.
Watch it as you feed a case up and mark the expander with a fineline sharpie.
Multiracer- Posts : 975
Join date : 2017-03-15
Location : North Ohio
Re: Expander diameter vs. crimp - a question
Failing the push test is a critical failure
As I recall, J.Keefer had one designed slightly larger than bullet dia and 66% depth.
It allowed neck tension on the base 33% only.
If I remember correctly.
As I recall, J.Keefer had one designed slightly larger than bullet dia and 66% depth.
It allowed neck tension on the base 33% only.
If I remember correctly.
james r chapman- Admin
- Posts : 6299
Join date : 2012-01-31
Age : 75
Location : HELL, Michigan
Re: Expander diameter vs. crimp - a question
Optical compensatorAprilian wrote:Chris, as the expanders are rounded on the bottom, how would I accurately measure the depth it goes into the case?
Chris Miceli- Posts : 2715
Join date : 2015-10-27
Location : Northern Virginia
Re: Expander diameter vs. crimp - a question
Knowledge from Jerrys post. Now I need someone to grinde an expander for my star
https://www.facebook.com/groups/216804568382563/permalink/1481699668559707/
https://www.facebook.com/groups/216804568382563/permalink/1481699668559707/
Chris Miceli- Posts : 2715
Join date : 2015-10-27
Location : Northern Virginia
Re: Expander diameter vs. crimp - a question
Or read the brass deposits.Multiracer wrote:mark the expander with a fineline sharpie.
total length impacting the case .300
.451 expansion length .230
.455 bell section (straight) .070
Rereading Jerry's Facebook post, I decided to measure the driving band on that bullet. It is .275 - looks like I need to back off some on the expander depth.
Last edited by Aprilian on Sat Jul 22, 2017 4:31 pm; edited 1 time in total
Aprilian- Posts : 987
Join date : 2016-05-13
Location : Minnesota
Re: Expander diameter vs. crimp - a question
What is the shoulder length in the bullet?Aprilian wrote:Or read the brass deposits.Multiracer wrote:mark the expander with a fineline sharpie.
total length impacting the case .300
.451 expansion length .230
.455 bell section (straight) .070
Chris Miceli- Posts : 2715
Join date : 2015-10-27
Location : Northern Virginia
Re: Expander diameter vs. crimp - a question
Chris, I believe the contraption for magnification is an optical comparator.Chris Miceli wrote:Optical compensatorAprilian wrote:Chris, as the expanders are rounded on the bottom, how would I accurately measure the depth it goes into the case?
Multiracer- Posts : 975
Join date : 2017-03-15
Location : North Ohio
Re: Expander diameter vs. crimp - a question
Damn auto correctMultiracer wrote:Chris, I believe the contraption for magnification is an optical comparator.Chris Miceli wrote:Optical compensatorAprilian wrote:Chris, as the expanders are rounded on the bottom, how would I accurately measure the depth it goes into the case?
Chris Miceli- Posts : 2715
Join date : 2015-10-27
Location : Northern Virginia
Re: Expander diameter vs. crimp - a question
better than my bosses email that it was time for my anal exam.Chris Miceli wrote:Damn auto correctMultiracer wrote:Chris, I believe the contraption for magnification is an optical comparator.Chris Miceli wrote:Optical compensatorAprilian wrote:Chris, as the expanders are rounded on the bottom, how would I accurately measure the depth it goes into the case?
![lol!](https://2img.net/i/fa/i/smiles/lol.gif)
james r chapman- Admin
- Posts : 6299
Join date : 2012-01-31
Age : 75
Location : HELL, Michigan
Page 1 of 2 • 1, 2
![-](https://2img.net/i/empty.gif)
» expander diameter for 45acp
» Correct diameter expander for 45 acp lead
» Crimp question
» Crimp question !!!
» Question about tight crimp
» Correct diameter expander for 45 acp lead
» Crimp question
» Crimp question !!!
» Question about tight crimp
Page 1 of 2
Permissions in this forum:
You cannot reply to topics in this forum
|
|