I am loading 9mm for the first time. Using Accurate Arms #7 and lead cast 125 gn round nose bullet. AA load data shows 7.4 grs powder and COL of 1.095". My factory Winchester 115 gn cartridges (WWB) have a COL of 1.16". This seems like quite a difference and the bullets seems seated too far. But it is per AA load data. Does this sound right?
Question on loading 9mm
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rfwobbly
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Does this sound right? Yes.
Rule #1. I'm not a user of AA7, but the powder load AND the OAL work together to create the pressure. You've got to remember that. So that if the Winchester at the longer length was also using AA7 (just for instance), it might have slightly more powder for the same pressure. Follow?
Rule #2. If that was the only number the AA data chart gave, then you'll want to start loading at 10% less. So 7.4 minus .74 equals ~6.7gr. 6.7 would be your starting load, and 7.4 would be the max load. Do not take chances. Start low.
Rule #3. Furthermore, you can usually increase the OAL for a given load in small increments, since that would reduce pressure. So let's say you load ten rounds at 6.7 and ten at 6.8, etc, and find your best shooting with AA7 is at 6.9gr at 1.095". You might try 6.9gr at 1.100" to see if they feed better.
A longer cartridge may feed better; a shorter cartridge is going to use less powder. It's s trade-off you decide on.
Rule #4. The 9mm being the cartridge with one of the smallest case volumes means that very small changes have much greater effects than any other cartridge. So please make VERY small adjustments as you go. Remember: No large jumps in OAL or powder loads.
Hope this helps!
Rule #1. I'm not a user of AA7, but the powder load AND the OAL work together to create the pressure. You've got to remember that. So that if the Winchester at the longer length was also using AA7 (just for instance), it might have slightly more powder for the same pressure. Follow?
Rule #2. If that was the only number the AA data chart gave, then you'll want to start loading at 10% less. So 7.4 minus .74 equals ~6.7gr. 6.7 would be your starting load, and 7.4 would be the max load. Do not take chances. Start low.
Rule #3. Furthermore, you can usually increase the OAL for a given load in small increments, since that would reduce pressure. So let's say you load ten rounds at 6.7 and ten at 6.8, etc, and find your best shooting with AA7 is at 6.9gr at 1.095". You might try 6.9gr at 1.100" to see if they feed better.
A longer cartridge may feed better; a shorter cartridge is going to use less powder. It's s trade-off you decide on.
Rule #4. The 9mm being the cartridge with one of the smallest case volumes means that very small changes have much greater effects than any other cartridge. So please make VERY small adjustments as you go. Remember: No large jumps in OAL or powder loads.
Hope this helps!
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My approach to 9mm is to make the OAL of the loads as long as will reliably feed and will not contact the rifling.
First, take the barrel out of your gun and prepare some dummy rounds (no powder or primers) at the maximum OAL. Drop a round into the chamber and see if it goes all the way in. If not, shorten it a few thousandths and try again. Once it clears the rifling, you may shorten by a couple thousandths more.
Then load the dummy round in a magazine and, with the slide locked back, release the slide and watch how it feeds. If it feeds smoothly (click), that's good. If it feeds with a "click-click", you may want to shorten the load a few thousandths more. If it hangs up, you need to rethink the OAL, bullet shape, feed ramp contour, or other factors.
Do this with one round in the mag and try again with eight or ten rounds in the mag. (The differences in mag spring tension may affect feeding.) If it still feeds fine, go on to the next step.
In a 9mm, it is vital that the bullet does not push back during feeding. Repeat the above process a couple of times and re-check the AOL. If it remains the same, you are set. If the OAL is smaller after a try or two, check your crimp, brass, and bullet size before proceeding further.
Then reload 20 or 30 bullets at that length and try them at the range. If they work, write down the OAL with that bullet. If you change bullets, you should repeat all the above steps.
Chris
First, take the barrel out of your gun and prepare some dummy rounds (no powder or primers) at the maximum OAL. Drop a round into the chamber and see if it goes all the way in. If not, shorten it a few thousandths and try again. Once it clears the rifling, you may shorten by a couple thousandths more.
Then load the dummy round in a magazine and, with the slide locked back, release the slide and watch how it feeds. If it feeds smoothly (click), that's good. If it feeds with a "click-click", you may want to shorten the load a few thousandths more. If it hangs up, you need to rethink the OAL, bullet shape, feed ramp contour, or other factors.
Do this with one round in the mag and try again with eight or ten rounds in the mag. (The differences in mag spring tension may affect feeding.) If it still feeds fine, go on to the next step.
In a 9mm, it is vital that the bullet does not push back during feeding. Repeat the above process a couple of times and re-check the AOL. If it remains the same, you are set. If the OAL is smaller after a try or two, check your crimp, brass, and bullet size before proceeding further.
Then reload 20 or 30 bullets at that length and try them at the range. If they work, write down the OAL with that bullet. If you change bullets, you should repeat all the above steps.
Chris
7.4 to 8.2grs of AA#7 is the load range for a 125gr LRN. While they recommend 1.095" in their data AA#7 fills a 9mm case pretty full and I'd be surprised if the load isn't compressed. Their OAL may be a minimum.
Part of reloading is trying and seeing how things work. Load up some at AA's OAL and some longer and see if one works and shoots better than the other.
Part of reloading is trying and seeing how things work. Load up some at AA's OAL and some longer and see if one works and shoots better than the other.
Jenrick
Member
For pistol calibers I've always just loaded up a dummy round, with lighter then normal neck tension (no crimp or anything), and chambered it with the full force of the slide slapping it into the chamber. From there if the COL isn't below the min COL I just use that. The slide ramming the cartridge home will push the bullet back if it's set too long. I've never had feeding problems.
-Jenrick
-Jenrick
The shape of the bullet will also determin the max oal. The more pointed Win fmj can be loaded longer then a more rounded lead rn. Every time you change bullet type, you must find a new oal, for it. HPs and flat points really have a short oal, but there may be the same amount of bullet inside the case. You gotta watch both ends
I use 8rings method on finding max oal, but use a fired case so the bullet moves easily by hand. I just start a bullet in the case, and push it slowly into the chamber by hand, letting the rifling seat the bullet, remove and measure. Subtract .010 from the reading, and use this for your max oal.
I use 8rings method on finding max oal, but use a fired case so the bullet moves easily by hand. I just start a bullet in the case, and push it slowly into the chamber by hand, letting the rifling seat the bullet, remove and measure. Subtract .010 from the reading, and use this for your max oal.
If you want to use an Accurate powder I would recommend AA #5 over AA #7 for cast bullets unless you want to push them real fast. It will use less powder to get the same velocities, and it won't be a compressed load.
I pick an O.A.L. that feeds well with whatever bullet I am using. Then I go from there. Test function while testing the lighter loads when working up.
After you pick an O.A.L. your pistol likes work your load up from there taking into consideration wether your O.A.L. is longer or shorter than the one used to get the pressure data.
I pick an O.A.L. that feeds well with whatever bullet I am using. Then I go from there. Test function while testing the lighter loads when working up.
After you pick an O.A.L. your pistol likes work your load up from there taking into consideration wether your O.A.L. is longer or shorter than the one used to get the pressure data.
armoredman
Member
I usethat OAL in my 9mm cast loads with AA#7, 125gr cast LRN Lee mould, good stuff. Another good powder is AA#2, for cast, in my experiance.
It can be fun finding the right load, but it's worth it!
It can be fun finding the right load, but it's worth it!
Marlin 45 carbine
Member
Bullseye does well with cast slugs in my 9mm Para, ,32acp, .380acp and 9X18 Makarov. cheap too.
rfwobbly
Member
Good point. Dealing with "compressed loads" is NOT something you want to do as a beginner. You can use the butt end of your caliper to make a depth measurement from the case mouth down to the powder level.
Then add the bullet length to .750, and then subtract the OAL. That will tell you the bullet's insertion depth. If the depth is lower than the measured powder level your bullet is compressing the powder... which is a BAD thing.
If that's the case, you'd do well to move to a longer OAL or change powder.
Compressed (reasonably so) charges are fine with most powders, but not something beginners should fool with. That is one reason I suggested AA #5 instead if he wanted to stick with Accurate powders. WSF, N330 or Unique are also good choices.
armoredman
Member
Today, I used a light load of 6.4gr of AA#7 at 1.095, under my own cast 125gr LRN, sized .356, light LLA. At 11 paces, this load was a tack driver in my P01, and dropped the empties in a neat pile. No malfunctions whatsoever. Light load, to be sure, but worked perfectly.
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