Bottom Gun
Member
Yes, there are some variables involved including your sizing die.
Sharing some 357sig test data
- Thread starter vaalpens
- Start date
- Status
Yes, there are some variables involved including your sizing die.
OP
OP
vaalpens
Member
- Joined
- Aug 14, 2014
- Messages
- 2,618
I did perform a quick test today:
Used 4 RMR 124gr FMJFN bullets
Selected 4 Speer cases with the same length .8565" (the shortest I could find).
Chamfered 2 (#1 and #2) of them and expanded 2 (#3 and #4) of them.
Seated them on a single stage press with the following COL:
#1: 1.1400"
#2: 1.1405"
#3: 1.1400"
#4: 1.1415"
The COL was measured by rotating the case and taking multiple reading. The lowest COL was recorded.
I then crimped the #3 and #4 dummy rounds and measured the COL again. No change.
Next step was to load 1 dummy round, lock the slide back, and released the slide. 4 Times for each dummy round. The COL was measure after the 4 cycles through the gun.
#1: 1.1395"
#2: 1.1400"
#3: 1.1390"
#4: 1.1410"
Then I took each dummy round and pushed it down on a bathroom scale. For this test I have to hold it for about 5 seconds before the digital scale will register. This is why the pressure applied is not the same for all rounds:
#1: 22.4lb
#2: 25.8lb
#3: 28.8lb
#4: 27.2lb
I then measured the bullets again.
#1: 1.1400"
#2: 1.1400"
#3: 1.1390"
#4: 1.1415"
You can see there is some fluctuation of the COL, but it is probably just because of the way I measured it, except maybe for #3. All these dummy rounds passed my test and I don't think I could detect any difference. The only difference I did see was that placing the bullet on the chamfered case was more difficult. You have to be more precise.
At some point I will probably take one of my know loads and load some live rounds and test them. Maybe there will be a difference in the chrono numbers or groupings.
Used 4 RMR 124gr FMJFN bullets
Selected 4 Speer cases with the same length .8565" (the shortest I could find).
Chamfered 2 (#1 and #2) of them and expanded 2 (#3 and #4) of them.
Seated them on a single stage press with the following COL:
#1: 1.1400"
#2: 1.1405"
#3: 1.1400"
#4: 1.1415"
The COL was measured by rotating the case and taking multiple reading. The lowest COL was recorded.
I then crimped the #3 and #4 dummy rounds and measured the COL again. No change.
Next step was to load 1 dummy round, lock the slide back, and released the slide. 4 Times for each dummy round. The COL was measure after the 4 cycles through the gun.
#1: 1.1395"
#2: 1.1400"
#3: 1.1390"
#4: 1.1410"
Then I took each dummy round and pushed it down on a bathroom scale. For this test I have to hold it for about 5 seconds before the digital scale will register. This is why the pressure applied is not the same for all rounds:
#1: 22.4lb
#2: 25.8lb
#3: 28.8lb
#4: 27.2lb
I then measured the bullets again.
#1: 1.1400"
#2: 1.1400"
#3: 1.1390"
#4: 1.1415"
You can see there is some fluctuation of the COL, but it is probably just because of the way I measured it, except maybe for #3. All these dummy rounds passed my test and I don't think I could detect any difference. The only difference I did see was that placing the bullet on the chamfered case was more difficult. You have to be more precise.
At some point I will probably take one of my know loads and load some live rounds and test them. Maybe there will be a difference in the chrono numbers or groupings.
Last edited:
OP
OP
vaalpens
Member
- Joined
- Aug 14, 2014
- Messages
- 2,618
I performed a final test yesterday by pulling the bullets using my RCBS kinetic bullet puller.
The way I normally use the kinetic puller is on concrete, using a tap, tap and a hit. This normally gives me an idea how good the neck tension is. I count a tap, tap, hit as one hit. Following are the results:
#1: 5 hits
#2: 5 hits
#3: 6 hits
#4: 5 hits
The above results all depends on how consistent I am with the taps and hits, so I would think the neck tension is probably the same for both chamfer and expansion/crimp.
The way I normally use the kinetic puller is on concrete, using a tap, tap and a hit. This normally gives me an idea how good the neck tension is. I count a tap, tap, hit as one hit. Following are the results:
#1: 5 hits
#2: 5 hits
#3: 6 hits
#4: 5 hits
The above results all depends on how consistent I am with the taps and hits, so I would think the neck tension is probably the same for both chamfer and expansion/crimp.
- Status
