Just got my 9mm bullets today and started loading...pulled my barrel from my 92fs and kind of confused as to checking headspace with this type of barrel...any suggestion?...I know there are other guys who have this type of handgun and have the answer...thanks for any help
how do you figure headspace for Berreta 92 fs..
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rcmodel
Member in memoriam
You are not checking headspace.
You are checking cartridge OAL to insure the bullet isn't jamming into the rifling leade when the slide slams shut.
Take the barrel out of the gun and use it for the OAL gage.
Drop a long seated cartridge in the chamber and keep seating shorter until the bullet clears the rifling and the case head is even with the back of the barrel.
rc
You are checking cartridge OAL to insure the bullet isn't jamming into the rifling leade when the slide slams shut.
Take the barrel out of the gun and use it for the OAL gage.
Drop a long seated cartridge in the chamber and keep seating shorter until the bullet clears the rifling and the case head is even with the back of the barrel.
rc
Matt Dillon
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rcmodel
Member in memoriam
Case gages don't check the most critical measurement.
That being, whether the bullet profile you are using hits the rifling in the barrel you are using at the OAL you are using.
Only the barrels chamber from the gun can tell you that.
rc
That being, whether the bullet profile you are using hits the rifling in the barrel you are using at the OAL you are using.
Only the barrels chamber from the gun can tell you that.
rc
floydster
Member
I never use a case gauge, always the barrel--listen to rc
1SOW
Member
rc +2
IF you want to know the "headspace" for a given BULLET;
Seat the bullet by hand in a "spent" case that has NOT been resized. Just push the bullet in far enough to hold itself in place.
Then carefully push this dummy round into the naked chamber until it seats on the case mouth.
Turn the bbl up and carefully remove the dummy rd and measure it.
Do this three or four times for a consistant measurement.
THIS LENGTH is hitting the rifling or chamber wall. Anything LESS than this length gives you the amount of "headspace" before contact with the rifling or chamber wall.
Every different bullet gives a different oal to "contact" with the chamber/rifling.
EEZEE.
IF you want to know the "headspace" for a given BULLET;
Seat the bullet by hand in a "spent" case that has NOT been resized. Just push the bullet in far enough to hold itself in place.
Then carefully push this dummy round into the naked chamber until it seats on the case mouth.
Turn the bbl up and carefully remove the dummy rd and measure it.
Do this three or four times for a consistant measurement.
THIS LENGTH is hitting the rifling or chamber wall. Anything LESS than this length gives you the amount of "headspace" before contact with the rifling or chamber wall.
Every different bullet gives a different oal to "contact" with the chamber/rifling.
EEZEE.
gamestalker
member
This is a good time to help you learn some things about rimless cartridges, such as 9mm. How deep you seat the bullet is referred to as casing over all length, or COAL / OAL, and has nothing to do with head space, what so ever.
My method for finding the right seating depth for my AL's, is I first determine the longest OAL that will fit the magazine, and makes, or just begins to make contact with the lands. So in other words if a cartridge fits the magazine, but the bullet is jamming into the lands, I need to seat it deeper until it just clears the lands, that is my max OAL. Next I locate an OAL that is above the published minimum, and cycles 100% reliably. I like to determine my maximum powder charge when I'm up at the longest OAL, that way as I decrease the OAL, I can stay focused on OAL, rather than having to adjust powder charges throughout the OAL process. Once I've got OAL figured out, I work the powder charge up incrementally until I'm satisfied with the velocity.
Having loaded for the 92FS for at least 20 yrs. now, I haven't identified any quirks, or other wise discovered any particular challenges. In fact, everything I load for my other 9mm's, functions just fine through the 92 FS, and visa, versa.
Head space is measured from the case head to the mouth of the case. And with rimless cartridges, head space is controlled by brass trim length. Brass that is too short will seat too deep in the chamber, and can cause mis-fires. Where as brass that is too long, and in need of trimming, can cause the firearm to fail to go into battery.
And if rimless cartridges are over crimped, it can allow the case mouth to get pinched or wedged in the throat, thus causing pressures to sky rocket unpredictably high.
GS
My method for finding the right seating depth for my AL's, is I first determine the longest OAL that will fit the magazine, and makes, or just begins to make contact with the lands. So in other words if a cartridge fits the magazine, but the bullet is jamming into the lands, I need to seat it deeper until it just clears the lands, that is my max OAL. Next I locate an OAL that is above the published minimum, and cycles 100% reliably. I like to determine my maximum powder charge when I'm up at the longest OAL, that way as I decrease the OAL, I can stay focused on OAL, rather than having to adjust powder charges throughout the OAL process. Once I've got OAL figured out, I work the powder charge up incrementally until I'm satisfied with the velocity.
Having loaded for the 92FS for at least 20 yrs. now, I haven't identified any quirks, or other wise discovered any particular challenges. In fact, everything I load for my other 9mm's, functions just fine through the 92 FS, and visa, versa.
Head space is measured from the case head to the mouth of the case. And with rimless cartridges, head space is controlled by brass trim length. Brass that is too short will seat too deep in the chamber, and can cause mis-fires. Where as brass that is too long, and in need of trimming, can cause the firearm to fail to go into battery.
And if rimless cartridges are over crimped, it can allow the case mouth to get pinched or wedged in the throat, thus causing pressures to sky rocket unpredictably high.
GS
thanks guys for all the information I'm new to this and don't know all the phrases to use when I ask questions ...headspace was the incorrect phrase I was looking for and col what is what I meant ...I loaded for the col that was in my lymans manual ...it loaded very good in my Ruger and cycle very well in the beretta just wanted to make sure I got it right...my questions might sound rookie ,but that's what I am ...
Captaingyro
Member
Be aware that, despite the dictum that rimless cartridges "headspace on the case mouth", this is actually true only in one (very rare) cirmumstance. That circumstance occurs when the chamber is reamed to the minimum depth, and a case is at the maximum allowable length. In all other circumstances, the depth of the cartridge's seating in the chamber is controlled by the extractor.
The techniques described above are all sound, and will work. But be aware that taking the barrel out of the gun and seating a round in the chamber will probably result in a round seated deeper than in the fully-assembled pistol. The extractor will almost always prevent a round from seating as deeply as it does during a "plunk" test.
The techniques described above are all sound, and will work. But be aware that taking the barrel out of the gun and seating a round in the chamber will probably result in a round seated deeper than in the fully-assembled pistol. The extractor will almost always prevent a round from seating as deeply as it does during a "plunk" test.
rcmodel
Member in memoriam
No, it won't.
In most pistol designs I am aware of, there is ample room between the case rim and the extractor hook to allow the rim to feed out of the magazine and slide up the breech face at an angle.
In a typical gun, there will be several thousandths clearance between the case rim and the hook when it is chambered. The hook itself will be setting on the bottom of the extractor groove in the case, but the back of the hook will not be in tight contact with the case rim.
That the extractor hook controls headspace in an auto pistil is simply an urban legend.
rc
gamestalker
member
What RC said.
If the brass didn't seat completely into the chamber one would very likely have constant mis-fires, and probably be replacing extractors very regularly too.
GS
If the brass didn't seat completely into the chamber one would very likely have constant mis-fires, and probably be replacing extractors very regularly too.
GS
+1
Also, keep in mind 9mm chambers are cut to a depth of .760" and 9mm cases are seldom longer than .750". In many cases they are .745" or shorter. 9mm pistols typically have .030" of clearance between the rim and the extractor hook. That leaves at least .010" of wiggle room. Therefore, even the shortest 9mmcase will headspace off the chamber end and not the extractor hook.
Further, Beretta 9mm chambers have .356"/.357" bores and .359" freebores so you can use .38/.357 bullets if you want.
Also, keep in mind 9mm chambers are cut to a depth of .760" and 9mm cases are seldom longer than .750". In many cases they are .745" or shorter. 9mm pistols typically have .030" of clearance between the rim and the extractor hook. That leaves at least .010" of wiggle room. Therefore, even the shortest 9mmcase will headspace off the chamber end and not the extractor hook.
Further, Beretta 9mm chambers have .356"/.357" bores and .359" freebores so you can use .38/.357 bullets if you want.
jolly roger
Member
Cast .358 140 grain Missouri Bullet "Zinger's" with a fairly light charge made my Beretta SHOOT after I heard they had large bores for caliber. Completely different animal with those.
LiveLife
Member
Many have posted Beretta 92s have larger groove diameter barrels.jolly roger said:
For oversized barrels, larger sized lead bullets would work better and probably decreasing leading too.
Captaingyro
Member
This is an "urban legend" that you can measure for yourself. Do this with a dummy round.
rfwobbly
Member
ALS 1911 -
The OAL in your manual is NOT a recommendation, it's merely a report of what was used during the testing. It's up to the reloader to find the OAL that works correctly in his/her barrel. While the reported OAL can be a good place to start, the last word is always given by the bullet-to-barrel fit.
Learning to navigate between the manual and the actual restrictions imposed by your gun is called "reloading". Welcome aboard!
The OAL in your manual is NOT a recommendation, it's merely a report of what was used during the testing. It's up to the reloader to find the OAL that works correctly in his/her barrel. While the reported OAL can be a good place to start, the last word is always given by the bullet-to-barrel fit.
Learning to navigate between the manual and the actual restrictions imposed by your gun is called "reloading". Welcome aboard!
1KPerDay
Member
FYI RC and to the OP, on the Beretta the bottom of the case will not be even with the back of the barrel when the mouth of the case seats against the chamber. if you have a Beretta handy, try it.
Owen
Moderator Emeritus
In my experience, most bullet profiles in 9mm will be far to long to fit in the magazine before they start to contract the rifling.
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