THR Group Project - PISTOL - Advanced Reloading Concepts and Discussions
- Thread starter LiveLife
- Start date
OP
OP
LiveLife
Member
I have been able to measure bullet setback. Has anyone been able to measure bullet pull in magazines?
you actually have to load em up and shoot em. measure the coal of a round, then put it in the magazine. load nine more rounds in the mag. shoot eight rounds, drop the mag and measure the coal again (be careful, round number nine is still in the chamber). reinsert the mag (with round no. ten) and shoot round no. nine. eject round ten from the chamber and measure again.
the second measurement will show bullet pull, if any. the third measurement will show both bullet pull and bullet setback.
murf
the second measurement will show bullet pull, if any. the third measurement will show both bullet pull and bullet setback.
murf
OP
OP
LiveLife
Member
Not what I was getting at.
OK, let's poll the THR audience.
By show of hands, how many of you have experienced bullet pull with semi-auto/magazine?
OK, let's poll the THR audience.
By show of hands, how many of you have experienced bullet pull with semi-auto/magazine?
OP
OP
LiveLife
Member
- COMPENSATE FOR MIXED RANGE BRASS CASE LENGTH VARIATION
It is my thinking that jell-dog now should use the barrel to determine the length where the case stops headspacing off the case mouth and starts to headspace on the extractor. Walkalong's thread has a great illustration to determine this - http://www.thehighroad.org/showthread.php?t=506678
Starting with the longer resized cases, check to see when the bottom of the case falls below the barrel's hood which makes contact with the breech wall (see picture below). Resized cases falling below the hood will not allow the breech wall to push the case mouth against the chamber when chambered but hang loosely off the extractor. If you are looking for accuracy, my suggestion would be to sort out these shorter cases.
Any thoughts on this notion?
jell-dog offered to send some sample of sorted brass for testing but here's my reply PM (I forgot to add the comment in brackets in the PM):jell-dog said:
If we were to use same length cases, this would not be necessary. IMO, case length variation of .001"-.002" is ideal to enhance accuracy.bds said:
It is my thinking that jell-dog now should use the barrel to determine the length where the case stops headspacing off the case mouth and starts to headspace on the extractor. Walkalong's thread has a great illustration to determine this - http://www.thehighroad.org/showthread.php?t=506678
Starting with the longer resized cases, check to see when the bottom of the case falls below the barrel's hood which makes contact with the breech wall (see picture below). Resized cases falling below the hood will not allow the breech wall to push the case mouth against the chamber when chambered but hang loosely off the extractor. If you are looking for accuracy, my suggestion would be to sort out these shorter cases.
Any thoughts on this notion?
Last edited:
Blue68f100
Member
^^^^^ Short cases can cause problems if your looking for ultimate accuracy.
If the bullet is controlling the head space it's not a good place to be. The shoulder (case mouth) should be control it. You don't want to count on the extractor to hold it. If not when the FP falls it will knock the bullet into the rifling... Plunk test is good but you need to know what your looking for. Most Mil guns have a generous chamber so contacting the rifling is hard to do. And a lot of them are over size too. I've had only had 1 gun (BHP 9mm) in which the OAL had any impact on accuracy. With it going to a shorter OAL reduced the group by 1/2.
If the bullet is controlling the head space it's not a good place to be. The shoulder (case mouth) should be control it. You don't want to count on the extractor to hold it. If not when the FP falls it will knock the bullet into the rifling... Plunk test is good but you need to know what your looking for. Most Mil guns have a generous chamber so contacting the rifling is hard to do. And a lot of them are over size too. I've had only had 1 gun (BHP 9mm) in which the OAL had any impact on accuracy. With it going to a shorter OAL reduced the group by 1/2.
horsemen61
Member
- Joined
- Oct 20, 2011
- Messages
- 6,755
tagg
OP
OP
LiveLife
Member
- DECREASING OAL/COL TO INCREASE NECK TENSION/INITIAL CHAMBER PRESSURE (9mm FMJ/RN SPECIFIC)
Bullets with substantial base or bearing surface (part of bullet that engages the rifling), like 45ACP 200 gr SWC and 40S&W 180 gr TCFP, can be seated to longer lengths without significantly decreasing the initial chamber pressure build for efficient enough powder burn (of course, this is my notion only so we can discuss it further if you like). BTW, I load 40S&W 180 gr TCFP longer than SAAMI max of 1.142"-1.155" depending on the bullet nose profile.
With 9mm 115 gr FMJ/plated RN and 124/125 gr lead RN with "stepped" nose (see picture below right of Dardas/ZCast bullets), this is an issue. Due to shorter bullet base, when these bullets are loaded long (say SAAMI max of 1.169"), IMO there may not be enough neck tension to create sufficient initial chamber pressure build up, especially if the expander is oversized or too much flare is used particularly with thinner walled cases. I have verified this by measuring bullet setback from feeding/chambering from the magazine when these factors "stack" on top of each other.
IME, using shorter 1.135" for 115 gr FMJ/plated RN and even shorter 1.125" for 124/125 gr "stepped" RN increases neck tension thus improve initial chamber pressure build up. I think this is the reason why "non-stepped" RN bullets such as MBC 124 gr RN (SmallBall) are sold instead of the stepped RN. In the picture above, you can compare the difference in bullet base/bearing surface of MBC RN vs Dardas/ZCast "stepped" RN.
Winchester 115 gr FMJ loaded to 1.135" showing "bulged case neck/Coca Cola bottle look" of tapered 9mm case to indicate good neck tension (cases full-length resized with Lee carbide die).
For my barrels, MBC RN needs to be seated to 1.080"-1.100" which puts substantial amount of bullet base inside the case neck for greater neck tension (remember, 9mm is a tapered case with thickening of case wall further down the case neck) not to mention longer bearing surface riding the rifling with bullet weight placed more towards the base (shifting of center of gravy towards the back like JHP bullets bullseye match shooter prefer for accuracy) for perhaps greater rotational stability in flight. If you want greater neck tension, it's hard to beat SWC with even more substantial bullet base.
MBC RN seated to 1.080" compared to 115 gr FMJ/125 gr CN/12 gr SWC
So is this the reason why many complain 9mm 115 gr bullet is less accurate than 124/125 gr? I think so, especially if you factor in mixed range brass with old brass that has less malleability from work hardening. BUT not all is lost. If you like the 115 gr bullet weight, Berry's MFG makes 115 gr thick plated bullet with hollow base that extends the bullet base/bearing surface. I have done comparison range test and I actually got smaller shot groups from 115 gr HBRN-TP bullet than 124 gr HBRN-TP in the 9mm Herco thread (I am still scratching my head over this one) - http://www.thehighroad.org/showthread.php?t=745656
Berry's 124 gr solid base, 124 gr HBRN-TP, 115 gr HBRN-TP and Winchester 115 gr FMJ
BTW, Dardas Cast Bullets offers both stepped 125 gr RN and non-stepped 124 gr RN bullets and offers 5% THR discount with HIGHROAD code - http://www.dardascastbullets.com/mm5/merchant.mvc?Screen=CTGY&Store_Code=dardas&Category_Code=9
Missouri Bullet Company offers non-stepped 124 gr RN (SmallBall) lubed/Hi-Tek coated and offers 5% THR discount with THR-Original code - http://www.missouribullet.com/results.php?category=5&secondary=8
Rocky Mountain Reloading offers 115/124 gr HM plated RN with harder 11-12 BHN lead alloy core with thicker plating (.012"-.014" vs Speer TMJ at .015") called "Hardcore Match" bullets at probably the lowest thick plated prices also with 5% THR discount with thehighroad5 code (Free shipping on all orders) - http://www.shop.rmrbullets.com/9mm-355_c12.htm
Powder Valley and TJConevera carry Berry's 115/124 gr HBRN-TP bullets (TJConevera with free shipping on $50+ orders).
This may go against the notion of longer OAL reducing high pressure gas leakage but IMO very pertinent to 9mm, especially with shorter bullets or bullet types with shorter bullet base/bearing surface.Blue68f100 said:
Bullets with substantial base or bearing surface (part of bullet that engages the rifling), like 45ACP 200 gr SWC and 40S&W 180 gr TCFP, can be seated to longer lengths without significantly decreasing the initial chamber pressure build for efficient enough powder burn (of course, this is my notion only so we can discuss it further if you like). BTW, I load 40S&W 180 gr TCFP longer than SAAMI max of 1.142"-1.155" depending on the bullet nose profile.
With 9mm 115 gr FMJ/plated RN and 124/125 gr lead RN with "stepped" nose (see picture below right of Dardas/ZCast bullets), this is an issue. Due to shorter bullet base, when these bullets are loaded long (say SAAMI max of 1.169"), IMO there may not be enough neck tension to create sufficient initial chamber pressure build up, especially if the expander is oversized or too much flare is used particularly with thinner walled cases. I have verified this by measuring bullet setback from feeding/chambering from the magazine when these factors "stack" on top of each other.
IME, using shorter 1.135" for 115 gr FMJ/plated RN and even shorter 1.125" for 124/125 gr "stepped" RN increases neck tension thus improve initial chamber pressure build up. I think this is the reason why "non-stepped" RN bullets such as MBC 124 gr RN (SmallBall) are sold instead of the stepped RN. In the picture above, you can compare the difference in bullet base/bearing surface of MBC RN vs Dardas/ZCast "stepped" RN.
Winchester 115 gr FMJ loaded to 1.135" showing "bulged case neck/Coca Cola bottle look" of tapered 9mm case to indicate good neck tension (cases full-length resized with Lee carbide die).
For my barrels, MBC RN needs to be seated to 1.080"-1.100" which puts substantial amount of bullet base inside the case neck for greater neck tension (remember, 9mm is a tapered case with thickening of case wall further down the case neck) not to mention longer bearing surface riding the rifling with bullet weight placed more towards the base (shifting of center of gravy towards the back like JHP bullets bullseye match shooter prefer for accuracy) for perhaps greater rotational stability in flight. If you want greater neck tension, it's hard to beat SWC with even more substantial bullet base.
MBC RN seated to 1.080" compared to 115 gr FMJ/125 gr CN/12 gr SWC
So is this the reason why many complain 9mm 115 gr bullet is less accurate than 124/125 gr? I think so, especially if you factor in mixed range brass with old brass that has less malleability from work hardening. BUT not all is lost. If you like the 115 gr bullet weight, Berry's MFG makes 115 gr thick plated bullet with hollow base that extends the bullet base/bearing surface. I have done comparison range test and I actually got smaller shot groups from 115 gr HBRN-TP bullet than 124 gr HBRN-TP in the 9mm Herco thread (I am still scratching my head over this one) - http://www.thehighroad.org/showthread.php?t=745656
Berry's 124 gr solid base, 124 gr HBRN-TP, 115 gr HBRN-TP and Winchester 115 gr FMJ
BTW, Dardas Cast Bullets offers both stepped 125 gr RN and non-stepped 124 gr RN bullets and offers 5% THR discount with HIGHROAD code - http://www.dardascastbullets.com/mm5/merchant.mvc?Screen=CTGY&Store_Code=dardas&Category_Code=9
Missouri Bullet Company offers non-stepped 124 gr RN (SmallBall) lubed/Hi-Tek coated and offers 5% THR discount with THR-Original code - http://www.missouribullet.com/results.php?category=5&secondary=8
Rocky Mountain Reloading offers 115/124 gr HM plated RN with harder 11-12 BHN lead alloy core with thicker plating (.012"-.014" vs Speer TMJ at .015") called "Hardcore Match" bullets at probably the lowest thick plated prices also with 5% THR discount with thehighroad5 code (Free shipping on all orders) - http://www.shop.rmrbullets.com/9mm-355_c12.htm
Powder Valley and TJConevera carry Berry's 115/124 gr HBRN-TP bullets (TJConevera with free shipping on $50+ orders).
Last edited:
ljnowell
Member
50cal
Member
Some thoughts....
I never use range brass. I buy new high-quality brass (i.e. Starline) and only reload it 1 - 3 times depending on the ammo produced. Case tension is virtually obsolete with good brass and not a variable you can reasonably control. Press down hard on the bullet if it moves toss it. Keep the feed ramp polished and the mag in tune. A little taper crimp is good for autos. Bullet "pull" is a consideration in heavy wheel gun loads but a custom cannula and a roll crimp alleviates that.
What matters too me....
Seating depth/OAL
Powder types (shape/burn rate/coating)
Crimps (taper/rolled)
Casings/Brass
Bullets (design/weights/cannulas/gas checks/lube)
Primers
Accuracy over chronograph
Twist and bullet weight
Saami is not factor, be responsible
Cheers!
I never use range brass. I buy new high-quality brass (i.e. Starline) and only reload it 1 - 3 times depending on the ammo produced. Case tension is virtually obsolete with good brass and not a variable you can reasonably control. Press down hard on the bullet if it moves toss it. Keep the feed ramp polished and the mag in tune. A little taper crimp is good for autos. Bullet "pull" is a consideration in heavy wheel gun loads but a custom cannula and a roll crimp alleviates that.
What matters too me....
Seating depth/OAL
Powder types (shape/burn rate/coating)
Crimps (taper/rolled)
Casings/Brass
Bullets (design/weights/cannulas/gas checks/lube)
Primers
Accuracy over chronograph
Twist and bullet weight
Saami is not factor, be responsible
Cheers!
Last edited:
OP
OP
LiveLife
Member
50cal, thanks for adding to the list of topics. Looks like we are mostly on the same page.
We did preface the use of new brass to reduce shot group size and reduction of flyers in the OP and the related thread link
We did preface the use of new brass to reduce shot group size and reduction of flyers in the OP and the related thread link
But since most of us use mixed range brass, we are discussing concepts that will enhance accuracy without the use of new brass or even verified once-fired brass.bds said:
OP
OP
LiveLife
Member
< post pending >
OP
OP
LiveLife
Member
OK, here's an updated draft of indexed list of topics. I separated the topics into:
- Reloading Practice
- Reloading Components
- Reloading Equipment
- Range Testing
Most open topics are still in the discussions phase and won't be closed for final linked post page until group consensus is OK'd.
Reloading Practice:
- MAX VS WORKING OAL/COL
Open - WORKING OAL/COL VS CHAMBERED OAL/COL
- SEATING DEPTH - OAL/COL
- WHEN TO USE SHORTER THAN MAX OAL/COL
Open - USING LONGER THAN SAAMI MAX LENGTH
Open - COMPENSATE FOR MIXED RANGE BRASS CASE LENGTH VARIATION
- CALCULATING BULLET SEATING DEPTH TO DETERMINE MAX CASE FILL
- CALCULATING POWDER CASE FILL TO AVOID COMPRESSED LOADS
Open - DECREASING OAL/COL TO INCREASE NECK TENSION/INITIAL CHAMBER PRESSURE (9mm FMJ/RN SPECIFIC)
- CRIMPS (Taper vs Roll)
- WHEN TO DOWNLOAD BELOW PUBLISHED START CHARGES
Reloading Components:
- POWER TYPES (Shape/Burn rate/Coating)
- BRASS CASE (Head stamp)
- BULLETS (design/weights/cannulas/gas checks/lube)
- PRIMERS BRANDS/SIZE DIFFERENCE/SEATING DEPTH
Reloading Equipment:
- POWDER CHARGE DROP VARIANCE
- ACCURACY OVER CHRONOGRAPH (MV/ES/SD)
- BARREL TWIST RATE/BULLET WEIGHT
- USING RESIZED/HAND PRIMED CASES IN PROGRESSIVE PRESSES
- HOW TO OBTAIN MORE CONSISTENT OAL/COL
- TUNING A BALANCE BEAM SCALE
- WHAT DIGITAL SCALES ARE NOT SUITABLE FOR RELOADING
Range Testing:
- POWDER WORK UP
Open - EVALUATING PISTOL LOADS
- Reloading Practice
- Reloading Components
- Reloading Equipment
- Range Testing
Most open topics are still in the discussions phase and won't be closed for final linked post page until group consensus is OK'd.
Reloading Practice:
- MAX VS WORKING OAL/COL
Open - WORKING OAL/COL VS CHAMBERED OAL/COL
- SEATING DEPTH - OAL/COL
- WHEN TO USE SHORTER THAN MAX OAL/COL
Open - USING LONGER THAN SAAMI MAX LENGTH
Open - COMPENSATE FOR MIXED RANGE BRASS CASE LENGTH VARIATION
- CALCULATING BULLET SEATING DEPTH TO DETERMINE MAX CASE FILL
- CALCULATING POWDER CASE FILL TO AVOID COMPRESSED LOADS
Open - DECREASING OAL/COL TO INCREASE NECK TENSION/INITIAL CHAMBER PRESSURE (9mm FMJ/RN SPECIFIC)
- CRIMPS (Taper vs Roll)
- WHEN TO DOWNLOAD BELOW PUBLISHED START CHARGES
Reloading Components:
- POWER TYPES (Shape/Burn rate/Coating)
- BRASS CASE (Head stamp)
- BULLETS (design/weights/cannulas/gas checks/lube)
- PRIMERS BRANDS/SIZE DIFFERENCE/SEATING DEPTH
Reloading Equipment:
- POWDER CHARGE DROP VARIANCE
- ACCURACY OVER CHRONOGRAPH (MV/ES/SD)
- BARREL TWIST RATE/BULLET WEIGHT
- USING RESIZED/HAND PRIMED CASES IN PROGRESSIVE PRESSES
- HOW TO OBTAIN MORE CONSISTENT OAL/COL
- TUNING A BALANCE BEAM SCALE
- WHAT DIGITAL SCALES ARE NOT SUITABLE FOR RELOADING
Range Testing:
- POWDER WORK UP
Open - EVALUATING PISTOL LOADS
Hangingrock
Member
Case length variation is a non issues for those that typically shoot 10 yards and under. Now if you are a Bullseye shooter at 50yds then its a consideration among other variables that affect accuracy potential.
If this is going to be "advanced" topics and deals with accuracy I do not see how case trimming can be thrown out. I also do not trim handgun brass and will not start.
That said it is a factor in all the variables that you have listed. Just as the same headstamp from the same lot. Again I do not deal with that for range shooting. Some guys do and only reload brass a few times.
There are so many variables, one can not disregard some of them.
For a true test of accuracy, the sample should be all the same brass (loaded the same number of times) at all the same case length.
When you say pistol only is that semi auto only or are revolvers included??
How many Angels can dance on the head of a Pin?
That said it is a factor in all the variables that you have listed. Just as the same headstamp from the same lot. Again I do not deal with that for range shooting. Some guys do and only reload brass a few times.
There are so many variables, one can not disregard some of them.
For a true test of accuracy, the sample should be all the same brass (loaded the same number of times) at all the same case length.
When you say pistol only is that semi auto only or are revolvers included??
How many Angels can dance on the head of a Pin?
OP
OP
LiveLife
Member
That may be the case but on this thread, we are investigating concepts that matter to those who want the smallest shot groups obtainable using mixed range brass, even at 10 yards.Hangingrock said:
BTW, here's a reminder from original post:
OP
OP
LiveLife
Member
So far, discussion has been for semi auto cases without trimming and like you, I won't trim semi auto cases.Rule3 said:
We have to draw the line somewhere. If you want to discuss the utmost accuracy at the level of bullseye match shooters, you could post on this thread - http://www.thehighroad.org/showthread.php?p=9606640#post9606640
My hope for this thread was to discuss more advanced reloading concepts beyond the basics using mixed range brass but not to the point of extreme practices used by bullseye match shooters due to cost and time constraints - http://www.thehighroad.org/showthread.php?p=9878555#post9878555
OK that is fine but to me makes no sense. I am not a bench rest handgun shooter but if you state:
Quote:
This thread is for reloaders who enjoy the minute details of reloading to OCD levels in pursuit of accuracy. If you are that person, come right in and post away. If utmost accuracy is not that important and minute of gong is good enough for you, read on.
Then not having the same brass or trimming it makes no sense. You are either OCD or not. You can not be partially OCD
but if you state:Quote:
This thread is for reloaders who enjoy the minute details of reloading to OCD levels in pursuit of accuracy. If you are that person, come right in and post away. If utmost accuracy is not that important and minute of gong is good enough for you, read on.
Then not having the same brass or trimming it makes no sense.
You are either OCD or not. You can not be partially OCD50cal
Member
A reloading conundrum.
Toprudder
Member
Toprudder
Member
I'm having a problem wrapping my mind around the concept of "bullet pull" in semi-autos. For that to happen, something has to hold the case and let the bullet float while the gun is being fired, like in a revolver. The only semi-auto that I can think of that would do that would be the Boberg pocket gun that pulls the rounds rearward out of the mag.
I've never experienced bullet pull in a semi-auto, but then again, it is not something I have considered looking for/measuring. If the bullet will pull, then setback can happen as well, and that is more what I am concerned about and what I actually check.
I've never experienced bullet pull in a semi-auto, but then again, it is not something I have considered looking for/measuring. If the bullet will pull, then setback can happen as well, and that is more what I am concerned about and what I actually check.
RugerOldArmy
Member
You could sort the brass.
GW Staar
Member
- Joined
- Feb 26, 2009
- Messages
- 3,691
BDS, I'll just say one thing......you are brave! But I'm interested (and curious).....I don't know that I've ever heard of benchrest pistol, but having a national ranked (Wilson sponsored) pistol shooter in my club, who routinely skunks everybody else I've see him shoot against, I'm interested in learning how he does that.....well beyond the permanent limitations caused by the fact that he is 30 something and I am 60 something. Shux, he tells his body to dive, roll, and shoot and it and his gun respond instantly and accurately. If I try that, it may or may not happen at all, let along accurately........and I'd have a hard time getting up with any style. That's putting it nice.
He reloads his own ammo and it shoots very well, obviously, but as far a advanced techniques.....I'm not sure about that.....but I WILL ask him. They have to hit the targets in competition, yes, but grouping them inside a 1/2" I'm not sure that's a need. (except in Hollywood) Someone please correct me if I'm stupid wrong.
But I'm interested (and curious).....I don't know that I've ever heard of benchrest pistol, but having a national ranked (Wilson sponsored) pistol shooter in my club, who routinely skunks everybody else I've see him shoot against, I'm interested in learning how he does that.....well beyond the permanent limitations caused by the fact that he is 30 something and I am 60 something. Shux, he tells his body to dive, roll, and shoot and it and his gun respond instantly and accurately. If I try that, it may or may not happen at all, let along accurately........and I'd have a hard time getting up with any style. That's putting it nice. He reloads his own ammo and it shoots very well, obviously, but as far a advanced techniques.....I'm not sure about that.....but I WILL ask him. They have to hit the targets in competition, yes, but grouping them inside a 1/2" I'm not sure that's a need. (except in Hollywood) Someone please correct me if I'm stupid wrong.
Last edited:
Mad Chemist
Member
I have only noticed bullet pull with magnum revolver loadings of heavy loads in .44mag. This was with 300gr bullets which had minimal clearance between the end of the cylinder and the chamber throat. I only noticed because it bound up the cylinder.
To be fair, I have never examined or measured for bullet pull in a semi auto. I do not load to the max working OAL. So if my semi autos experienced any bullet pull it was minimal enough to remain within the working OAL for my gun.
Similar threads
- Locked
- Sticky