9mm bullet setback
- Thread starter Reeferman
- Start date
- Status
OP
OP
Reeferman
Member
- Joined
- Jan 9, 2013
- Messages
- 1,259
What opinions is there on the powders I have for loading these 115 XTP? I have Bullseye, 231, HS-6 which Hornady #9 has loads for. I also have Tightgroup but no loads for it and the XTP.
I was going to start with 4.2 or 4.3 of Bullseye or 231. Or go with the slower HS-6.
I was going to start with 4.2 or 4.3 of Bullseye or 231. Or go with the slower HS-6.
It really depends on what you want the load to do. You can use data for any 115 Gr JHP, except for the Gold Dot, if they make one. Just make sure you are not seating deeper in the case, or adjust the data down if you are. Target/plinker load? Bullseye or W-231. Full velocity serious practice load? HS-6. Like your plinker load full velocity? HS-6.
Okay, first things first. If your screen name is any indicator of personal behavior, you should not be reloading. Period. Use of alcohol or drugs anywhere near the time of reloading is a recipe for future disaster. This is the first box on my reloading checklist; have you been alcohol-free for the length of time the FAA requires of pilots before they can fly and have you been free of illegal drugs for more than twice the duration of their half-lfe in the body?
Second thing, read the right column of the Speer manual that jmorris presented in post #15, i.e. the part he didn't underline.
Third, follow the OAL from published reloading manuals.
Fourth, an expander is used to open up the case mouth just enough to allow the bullet to be seated without collapsing the case wall. It should have little to nothing to do with neck tension if used properly.
Fifth, the 9mm headspaces on the case mouth and so should generally not be crimped. A light taper crimp may be necessary to eliminate excessive expansion of the case mouth, but should not be used to hold the bullet in place. See the Speer manual that jmorris included in post #15.
OP
OP
Reeferman
Member
- Joined
- Jan 9, 2013
- Messages
- 1,259
Ha ha ha ha I truly don't know what to say ha ha ha ha!!
Reefer
Man
REEFERMAN
I fully agree with what you say but hell I don't even drink I'm a refrigeration mechanic!!
LiveLife
Member
9mm cases should, generally, always be taper crimped.
an expander die is used to increase the inside diameter of the case to a consistent amount to ensure the bullet has a consistent diameter to be seated (consistent bullet pull). the case mouth expander portion of that die is required to bell the mouth of the case to prevent the shaving of lead bullets.
the oal in reloading manuals is specific to the bullet used in that manual. the reloader has to determine the correct oal for each bullet type.
i'm not going to comment on the drug and alcohol rant, other than use common sense about it when reloading. i wouldn't take a couple of doctor-prescribed oxycodone before reloading, for example, ymmv.
be careful and good luck,
murf
an expander die is used to increase the inside diameter of the case to a consistent amount to ensure the bullet has a consistent diameter to be seated (consistent bullet pull). the case mouth expander portion of that die is required to bell the mouth of the case to prevent the shaving of lead bullets.
the oal in reloading manuals is specific to the bullet used in that manual. the reloader has to determine the correct oal for each bullet type.
i'm not going to comment on the drug and alcohol rant, other than use common sense about it when reloading. i wouldn't take a couple of doctor-prescribed oxycodone before reloading, for example, ymmv.
be careful and good luck,
murf
I don't think this is the problem. Die manufacturers like to make flare dies 2 mil smaller than the bullet. This works ok for jacketed. But it's just flaring the mouth of the case, so the bullet can get started. Aside from the diameter, a standard expander die doesn't even reach far enough into a 9mm case to begin to cause this problem.
Rifle reloader that do careful trimming and neck sizing have discovered a long time ago that the proper ID of the neck should be about 2 mils smaller than the bullet to get maximum neck tension but without being too tight and causing unnecessary deformation of neck/bullet/shoulder when seating. But to get the ID of the case 2 mils smaller than the bullet, the expander has to be the same diameter as the bullet. That 2 mils is the approximate amount of stretch that the brass gives.
I got a 356 mil expander in 9mm for cast bullets. There's no setback. Even with jacketed 355 bullets.
+1 this is due to thin brass and/or large sizing die.
Last edited:
Reefinmike
Member
$110 for a set of rcbs carbide 9mm dies?
https://www.amazon.com/RCBS-20515-Carbide-9MMLUGER-9x21/dp/B000MOGSUKLee factory crimp dies are a bandaid fix looking for a problem. If your ammo wont chamber then your bullet is loaded too long, your brass is too thick or the bullets too large. Find the problem and address it. a FCD cannot add a single ounce of neck tension. Resizing the loaded round in a fcd can only reduce neck tension.
All pistol sizing dies must be set such that the shellholder just barely makes firm contact with the base of the die. It is especially important to have your dies set right with 9mm due to the nature of the tapered case.
HAHAHAHAHAHAHAH dont make assumptions about us "reefers"... I liked when THR started allowing avitar pictures so I could disambiguate my name for those that just assume. Alcohol killed well over 80,000 people in the US this year yet we as a society embrace it. One mention of cannabis and everyone is up in arms about the devil's weed... smh.
Dudedog
Contributing Member
I had issues with my Hornady 9mm resize die not sizing the case neck small enough. Switched to my 9mm Lee die and everything was fine. It is possible the resize decap die was causing you grief. Mine was in spec but on the loose side,
the Lee die is also in spec but on the tight side. As mentioned earlier watch out for thinner brass. Lots of variation in 9mm brass.
The Lee FCD and help or it can make things worse. Over crimping as mentioned earlier can swag the bullet down resulting in poor neck tension.
So you thing ah it's to loose need more crimp, when more crimp is actually making things worse.
the Lee die is also in spec but on the tight side. As mentioned earlier watch out for thinner brass. Lots of variation in 9mm brass.
The Lee FCD and help or it can make things worse. Over crimping as mentioned earlier can swag the bullet down resulting in poor neck tension.
So you thing ah it's to loose need more crimp, when more crimp is actually making things worse.
OP
OP
Reeferman
Member
- Joined
- Jan 9, 2013
- Messages
- 1,259
Well I loaded up 50 rounds with 4.2 grains of 231 and they all shot very well and no misfeeds. I checked for setback at various times from first to last round and the most I had was .003".
I also shot 50 rounds of American Eagle 115 as well and found no difference in accuracy so I'm pretty happy.
Before I loaded them the other day I measured a bunch of cases after sizing and made sure that the length of the cases I reloaded were all within .002".
So the question I have is what is the minimum and maximum case length that you all would allow while loading on a progressive press for range ammo?
I also shot 50 rounds of American Eagle 115 as well and found no difference in accuracy so I'm pretty happy.
Before I loaded them the other day I measured a bunch of cases after sizing and made sure that the length of the cases I reloaded were all within .002".
So the question I have is what is the minimum and maximum case length that you all would allow while loading on a progressive press for range ammo?
LiveLife
Member
You are measuring resized cases for length?
Good to hear. I don't worry about shortening of case length which happens gradually over time. When the case gets too short to headspace off case mouth, it will headspace off the extractor.
For plinking and range practice loads, slight variance in case length will be fine.
Good to hear. I don't worry about shortening of case length which happens gradually over time. When the case gets too short to headspace off case mouth, it will headspace off the extractor.
For plinking and range practice loads, slight variance in case length will be fine.
Blue68f100
Member
For brass length I do not measure any for hand gun, unless it's for a rimed case (38spl/357Mag) or my most accurate 45acp BE loads. For a completed round (OAL) I normally have a spread of 0.005" or less. Don't be surprised to see as much as 0.010" with some bullets. This is due to mfg and there is no way around it. With AP this is based with all stations full. This can vary depending on what caliber and the about of force needed to size. Even my 223R rounds are around 0.003" avg . When I load LSWC I use a modified seating die that's only contacts the shoulder. This way I do not contact the taper or top of the bullet giving a more consistent OAL.
The max is whatever the recommended "max" case length per the reloading manual. Most manuals state .750"/.751" for the 9mm.
The minimum case length would depend on the amount of adjustment you have on your crimp die. Not all brands of reloading dies are created equal.
You are dealing with 7/8-14 dies which are nothing more than a 7/8" bolt that takes 14 full turns to go 1 inch. This is why not all reloading dies are created equal. RCBS recommends a 1/8 turn down to taper crimp the 9mm's with their taper crimp die. Lee recommends 1/4 turn to 1/2 turn to crimp the 9mm's with their die.
1/8 turn ='s 14 x 8 or It takes 112 1/8 turns to go down 1 inch. 1" / 112 ='s .009"
1/4 turn ='s 14 x 4 or it takes 56 1/4 turns to go down 1 inch. 1" / 56 ='s .018"
1/2 turn ='s 14 x 2 or it takes 28 1/2 turns to go down 1 inch 1" /28 ='s .036"
Typically the minimum case length is 1/2 of whatever the crimp die is set to. Hence:
1/8 turn to crimp the 9mm's ='s .751" max and .751" - .0045" or .7465" minimum
1/4 turn to crimp the 9mm's ='s .751" max and .751" - .009" or .742" minimum
1/2 turn to crimp the 9mm's ='s .751" max and .751" - .018" or .733" minimum
At the end of the day it's a mechanical thing. How you setup your crimp die mandates the minimum oal of your cases. It does you no good to setup your crimp die for .751" cases and adjust your crimp down 1/8 turn and then try to load/crimp brass that is .742" to .745" long.
LiveLife
Member
I won't worry too much about finished OAL variation of a few thousandths. I do worry about neck tension/bullet setback and measure "Chambered OAL" by feeding dummy rounds from the magazine.
It doesn't matter how consistent your finished OAL is when the chambered OAL varies by .010"-.030" or more!
It doesn't matter how consistent your finished OAL is when the chambered OAL varies by .010"-.030" or more!
LiveLife
Member
About .002"+ for once-fired brass.
I posted compensating for case length variance on this post - https://www.thehighroad.org/index.p...concepts-and-discussions.778197/#post-9878562
Objective is to ensure shorter cases with more bullet nose sticking out will clear the start of rifling when chambered.
"The theoretical concept question is "Given the variation in case length of mixed range brass, how do we compensate to maximize our accuracy?"
The point I was trying to make in my response to jell-dog was given the case length variation in mixed range brass, we need to balance reliable feeding and chambering while trying to minimize high pressure gas leakage by using the longest OAL/COL.
Problem: Often, reloaders simply use the max OAL that will fully chamber in the barrel and spin without hitting the start of rifling. This could be the working OAL and sometimes not and shorter OAL needs to be used to reliably feed and chamber from the magazine. This is the true "Working OAL" that should be used for powder work up but given the variation in case length from mixed range brass, how do we know if our dummy round (no powder/no primer) was the right sample to determine the longest working OAL?
Solution: - Use shorter resized cases or subtract the case length variation from longer case lengths.
- Take a sample measurement of your resized brass (if you are OCD, measure all of them) to determine the range of variance. Why resized? Depending on the condition of brass/number of firings/amount of powder charge used, the resized case length will vary depending on how malleable/work hardened the brass is. For me, I have seen .002"+ to be the average of once-fired range brass.
- Use the shortest cases to make your dummy rounds to determine the working OAL as shorter cases will allow more of bullet nose to protrude above the case mouth to hit the start of rifling when chambered.
- Starting with max OAL, incrementally decrease the length until the dummy rounds reliably feed/chamber from the magazine.
- Or you can use the longest cases to determine the working OAL and subtract the case length variation to compensate."
I posted compensating for case length variance on this post - https://www.thehighroad.org/index.p...concepts-and-discussions.778197/#post-9878562
Objective is to ensure shorter cases with more bullet nose sticking out will clear the start of rifling when chambered.
"The theoretical concept question is "Given the variation in case length of mixed range brass, how do we compensate to maximize our accuracy?"
The point I was trying to make in my response to jell-dog was given the case length variation in mixed range brass, we need to balance reliable feeding and chambering while trying to minimize high pressure gas leakage by using the longest OAL/COL.
Problem: Often, reloaders simply use the max OAL that will fully chamber in the barrel and spin without hitting the start of rifling. This could be the working OAL and sometimes not and shorter OAL needs to be used to reliably feed and chamber from the magazine. This is the true "Working OAL" that should be used for powder work up but given the variation in case length from mixed range brass, how do we know if our dummy round (no powder/no primer) was the right sample to determine the longest working OAL?
Solution: - Use shorter resized cases or subtract the case length variation from longer case lengths.
- Take a sample measurement of your resized brass (if you are OCD, measure all of them
) to determine the range of variance. Why resized? Depending on the condition of brass/number of firings/amount of powder charge used, the resized case length will vary depending on how malleable/work hardened the brass is. For me, I have seen .002"+ to be the average of once-fired range brass.- Use the shortest cases to make your dummy rounds to determine the working OAL as shorter cases will allow more of bullet nose to protrude above the case mouth to hit the start of rifling when chambered.
- Starting with max OAL, incrementally decrease the length until the dummy rounds reliably feed/chamber from the magazine.
- Or you can use the longest cases to determine the working OAL and subtract the case length variation to compensate."
Last edited:
OP
OP
Reeferman
Member
- Joined
- Jan 9, 2013
- Messages
- 1,259
Great post Forest and that is what I'm trying to get to. I'm very aware of case min/max lengths, thread pitch and the mechanics of it.
Many say they never measure case length and will have hundreds or thousands of cases they picked up from range floor etc. Clean them using which ever method they use, they say they do not seperate by head stamp or case length and then start loading them on a progressive.
Some of the 9mm cases I measured were .010" to .012" different in length and many were the same head stamp. So then how are they being loaded with any consistency with regards to pressure, crimp or any accuracy?
Many say they never measure case length and will have hundreds or thousands of cases they picked up from range floor etc. Clean them using which ever method they use, they say they do not seperate by head stamp or case length and then start loading them on a progressive.
Some of the 9mm cases I measured were .010" to .012" different in length and many were the same head stamp. So then how are they being loaded with any consistency with regards to pressure, crimp or any accuracy?
they are not. mixed cases loaded on a progressive shot in a subcompact at a six inch plate at 7 yards don't need to be accurate. bump the distance to 50 yards in an accurate pistol and you have to start doing things different. bds has posted a lot on getting accuracy out of your pistol rounds. not everyone agrees on exactly what is required for those "ten shots into two inches at 50 yards". not everyone's accuracy requirements are this demanding.
just an fyi: accuracy has four parts: ammo, weapon, shooter, environment.
determine your accuracy requirement (it will change as you go along) and load accordingly.
luck,
murf
just an fyi: accuracy has four parts: ammo, weapon, shooter, environment.
determine your accuracy requirement (it will change as you go along) and load accordingly.
luck,
murf
LiveLife
Member
+1. "Accuracy" means different things to different shooters. For most shooters wanting to plink at 7 to 15 yards with minute of soda can accuracy, bullseye match level of accuracy (sub 2" groups at 50 yards) is not necessary.
With tapered 9mm case, this issue gets even more compounded and if you are looking for accuracy out of 115 gr bullets, ensuring consistent enough neck tension will not only reduce/minimize bullet setback but more consistent chamber pressure build for greater accuracy.
I believe for these reasons why Jake at Rocky Mountain Reloading decided to size their in-house 115 gr thick plated Hardcore Match RN bullets at .356" instead of typical .355". The larger bullet diameter will compensate for case length variation and resulting neck tension variation. On my 9mm carbine with mixed range brass thread, I did not experience bullet setback when OAL from 1.130" to 1.160" were tested.
I think best approach is to first measure for bullet setback after rounds are fed/chambered from the magazine. If there is no bullet setback or just a few thousandths, then for plinking loads, you should be OK. But if there is substantial bullet setback of more than .005"-.010"+, then reloading variables should be checked. If adjusting reloading variables do not improve neck tension, then using larger sized bullet may be the solution.
For me, the biggest issue with case length variance, especially 115 gr FMJ/RN bullets with shorter base loaded at longer OAL is consistency of neck tension and potential bullet setback and consistency of chamber pressure.
With tapered 9mm case, this issue gets even more compounded and if you are looking for accuracy out of 115 gr bullets, ensuring consistent enough neck tension will not only reduce/minimize bullet setback but more consistent chamber pressure build for greater accuracy.
I believe for these reasons why Jake at Rocky Mountain Reloading decided to size their in-house 115 gr thick plated Hardcore Match RN bullets at .356" instead of typical .355". The larger bullet diameter will compensate for case length variation and resulting neck tension variation. On my 9mm carbine with mixed range brass thread, I did not experience bullet setback when OAL from 1.130" to 1.160" were tested.
I think best approach is to first measure for bullet setback after rounds are fed/chambered from the magazine. If there is no bullet setback or just a few thousandths, then for plinking loads, you should be OK. But if there is substantial bullet setback of more than .005"-.010"+, then reloading variables should be checked. If adjusting reloading variables do not improve neck tension, then using larger sized bullet may be the solution.
OP
OP
Reeferman
Member
- Joined
- Jan 9, 2013
- Messages
- 1,259
I wish this site would inform that someone has posted before hitting the send button.
I think after reading what some of you who have far more experience at reloading 9 mm than me is I'm going to just load up some that I know have different case lengths then try chambering a few and check for setback.
If setback is minimal then I'll give them a go as I have 450 more left.
I think after reading what some of you who have far more experience at reloading 9 mm than me is I'm going to just load up some that I know have different case lengths then try chambering a few and check for setback.
If setback is minimal then I'll give them a go as I have 450 more left.
LiveLife
Member
And that's exactly why I started the "Carbine load testing with mixed range brass" thread - https://www.thehighroad.org/index.p...ass-plated-bullets-in-9mm-40s-w-45acp.799231/
Thankfully with help from Walkalong, I was able to develop loads that produced 1.5"-2" groups at 50 yards with 100 gr RMR Hardcore Match RN bullets. Who knew this was achievable with mixed range brass?
So yes, OCD level of headstamp sorting and measuring case length is not necessary to reload accurate enough plinking loads.
I switched from 22LR to 9mm carbines because I got tired of looking for 22LR ammunition and wanted to see if I could maximize accuracy with cheaper plated bullets I could reload at comparable cost to 22LR ammo. And no, I was not about to do any more sorting than cleaning/light polishing of brass in the tumbler.
Thankfully with help from Walkalong, I was able to develop loads that produced 1.5"-2" groups at 50 yards with 100 gr RMR Hardcore Match RN bullets. Who knew this was achievable with mixed range brass?
So yes, OCD level of headstamp sorting and measuring case length is not necessary to reload accurate enough plinking loads.
- Status
