Questions, Answered #7.....Headspace
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- čas přidán 1. 06. 2021
- What is headspace? This is the latest in a series of attempts to explain what it is, and isn't...
What we show is what you need to learn, not a tutorial. If you do not posses the skills to perform at this level, do NOT attempt. Support us: / anvil - Věda a technologie
That was the best illustration of the danger of 20 ga and 12 ga. so simple, yet not demonstrated that well often. Thanks!
This is, by far, the best explanation of "headspace" I've seen.
Thank you Mark. Decades of hunting and I never saw a 12 gauge shell stacked on 20 gauge shell. I never knew that danger existed. Thank you for pointing that out.
I'm not the first to point this out, but it does bear frequent repeating, eh?
@@marknovak8255 Absolutely! We are roughly the same age. (USMC ejection seats, F4 Phantom II) This made me say out loud, "that's scary". My son is a hunting guide in far south Texas. I sent him your video and told him to look for the danger at the end. Again, thank you Mark.
Mark, so most of your teaching sessions are as clear as Caribbean Water to me. This episode follows that same trail. From a Journeyman Gunsmith to a Master, Thank you so much.
12:26 The best visual explanation of why you should never carry your 20 ga with the 12 ga ammo.
I was showing a friend how people disagree on Foster slugs through a full choke. Forum discussions are useful for that, but ran into this 20 gauge into a 12 gauge danger. It's something he needs to keep in mind, he now owns both gauges.
9mm Luger will headspace on the 7.63 Mauser neck in the chamber and will lock up. When I used to reload I drilled holes in a new 9mm Luger case then primed and seated a new copper jacketed bullet designed for the 9mm
Luger in the case mouth sans powder and went to a safe area loaded this safed cartridge in the 7.63 Mauser pistol chamber and pulled the trigger. The empty, primed 9mm Luger case headspaced properly and fired but again it had no powder and had holes drilled in the case sides so the primer gasses could vent. The danger is clear and present; a live 9mm Luger round can chamber, properly headspace in a 7.63mm Mauser chamber and fire. One must take care when working around different firearms with similar chamber measurements. The results could end in loss of life.
@keith moore No, 9 Para(9x19) is .30 LUGER opened up. .30 Mauser (7.62x25/ 7.62x25/Tokarev) is longer, but shares a similar enough headsize and other geometry. 9mm Mauser Export was 9x25
Thank you for the definition. I was hoping that the 20ga - 12ga conundrum would come up. I was taught in 7th grade (1971???) that little piece of info. Never carry mixed shotgun rounds EVER! The Hawkeye Outdoors club was an after school (at school) club in our little town in Iowa. We got our hunters safety class and cards, made fishing rods (and then took a few field trips to use them), learned the hows and whys of shotgun reloading, (and shot some trap) an Most of all Firearms Safety. Thanks for the repeat lesson. There are some things that can't be said enough.
Thank you again and I'll keep watching.
Always was amused by the idea of having anything other than 12ga, since half the point of a shotgun in the day was to be versatile, saving you needing a big rack of specialized weapons. Shooting medium game? Buckshot. Shooting birds? Birdshot. Surprised by an angry boar? Slugs. Really can't find a purpose to smaller shotguns that is not done better by a .22'' rifle of some kind, because if you are trying to get rid of small birds and critters in your garden, you don't want a bunch of shot tearing through your plants to hit the animal you are trying to stop from eating your plants!
@@genericpersonx333 Well, .410 is an experts practice tool.
20ga is for teaching people how to shoot if they're not quite used to recoil.
In this case of the case-less round, sounds like a Sherlock Holmes film starring Mark Novak as Sherlock, Bruno as Watson and Othias as inspector Lestrade, special guest Mae as Mrs. Hudson. 🧐
seeing that 20 gauge drop perfectly in front of that 12. just about stopped my heart
Very clearly explained. Thank you. PS: The 20 gauge shell dropped in the 12 gauge barrel made the hair on the back of my neck stand up. Wow.
thank you sir that was one of the best explanations of headspace i've ever heard... i learn something with every one of these i watch...thank you again for taking the time to pass on your knowledge and craftmanship
@11:45 yep, and I've even had a guy get pissy with me when I asked him not to smoke next to me shooting black powder at the range. He wasn't even using the bench near me, he just came up to chat smoking a cig.
The last asswhippin I got from my daddy: I got home from high school and loaded a box of 12 ga so I could go hunting with the boys. Had a double charge at some point. Dropped it out in the big glass ashtray on the bench. Went hunting. Returned home to a very angry father with singed eyebrows and beard. Lesson learned.
LOL, was that incentive for him to quit smoking? Thanks for the story!
@@UtSlpilot no, but it got my ass warmed up pretty good.
How long did it take before you could sit down again? 😆
@@ScottKenny1978 not too long. I was a dumbass kid who did a dumbass kid thing. Taught me respect for the stuff though.
0.003" = 0.0762mm
Thank you Mark
I figured 76 microns and some. It's a handy measure of thumb, the micron - a couple either way doesn't make a lot of difference.
I was told that most commercial parts are good for plus or minus 50 microns. Gives within being right to 0.1mm, which is a little over 3 thousands of an inch for play.
A Swiss watch maker would read this and laugh though. :)
Damn! You dropped that 20 gauge into the chamber and then the 12 gauge in top of it and the hair on the back of my neck stood up. I had NO idea that was possible. Luckily I have only shot 12 gauge but WOW!!! Thank you VERY much for sharing all your hard earned knowledge and please continue to share it with us.
The 5th way is the .357 Sig, which cannot decide whether it wants to headspace on the shoulder or the case mouth.
And the 6th way is a 357SIG round in a 40S&W barrel; headspaces on the extractor!
@@musolinoa or .40s&w in a 10mm barrel
The Daisy caseless ammo was ignited by the heat of the air compressed when its spring was released. No primer needed. en.wikipedia.org/wiki/Daisy_V/L
The wonders of the metric system:
If .30 caliber (=0.3") is 7.62mm, which most people know, what is 0.003"?
Right, 0.0762mm ...
It's easy working with bases of 10, just move the decimal (in this case, simply add 2 zeros).
decimal inch works the same way
Wonders of math really. Of course, the real fun with any system like Metric begins when you have to divide by three. Indeed, tenths are great until you have a third person asking for a slice of the pie, which is why Greeks went with 360 when doing that circle thing. Really makes fractions easier.
Personally, I like having multiple measures, because you can choose what works best for every occasional instead of having to force a system to do everything. It is not like it is that hard to remember 12 inches to the foot, 3 feet to the yard. No more difficult than remembering the difference between a decameter and a decimeter.
Time flies: Daisy's caseless ammo came out more than 50 years ago - not 30 or 40.
Mark, Thank you for the Education on Headspace...Thank You For Your Service...God Bless...
Thank you very much for the VERY concise explanation of head space. .003" is equa to .076mm, FYI.
7mm Remington Magnum? Probably my favorite hunting caliber for Mule Deer - Elk.
Not having a set of GO/NO GO/FIELD Gauges for everything, I made my own rig. A empty case, cleaning rod and a magnetic based dial indicator can be cobbled together to get a pretty accurate measurement of headspace.
Hot damn. I've spent my life always hearing "rimless headspaces on the shoulder" with really no more explanation than that. But now it makes so much more sense why case gauges are so important to reloading when you do modern rifle rounds and what the adjustments on your sizing dies do to the case to make it fit a chamber. And I don't think I've cringed so hard as I did when you dropped that 12 on a 20 and it swallowed both. I never knew that.
Just built my first Remage 700. Go and No-Go gauges both checked about 43 times. All fired cases (458 SOCOM) fit into the chamber check gauge like sized new brass. This topic has been on my mind...
4 types of limiting surfaces preventing forward movement of cartridge case in a chamber = a datum or register.
Headspace, distance of aft abutting contact surface of a closed & locked breech (bolt face) to that register.
The relationship of locked bolt face to aft surface of cartridge (while registered) = clearance (go).
Relationship of jammed (not quite freely locked) bolt face to aft cartridge (registered) surface = interference (no go).
Relationship of spring force applied bolt face to aft cartridge surface (registered) surface = perfect!
Way to go Mark, I like your simple comprehensive explanation with sketches better!
Great video. I learned a lot and feel like I understand headspace a lot better now, in a way that will come in very handy for a lot of reasons. Also good to know about shotgun shells and black powder. Thanks!
Could you make something discussing go and no go gauges ?would make a excellent part 2
Great explanation of headspace, simple but easy to understand. In my opinion he is the man when it comes to firearms knowledge. Love his videos, learn something new from each one.
Best teacher ever! Anvil Gunsmithing and Technology School for Advanced Thinkers should be a thing!
Love this guy. Thank you
Thanks, Mark, for the clarification!
It's a distinct pleasure to learn from this man...
BRAVO ZULU, SIR!!!
Chuck in Michigan
U.S. Navy Retired
Every single one of your videos I watch, makes me want to become a gunsmith more and more.
12:48 At this moment my eyebrows hit the ceiling as the realization hit me of how bad that would be.
Kaboom.
Mark, this is the absolute best example/definition of head space I've ever watched. Thank you. Judging by your handwriting you used to be a Dr. Didn't you lol.
he'll get that heart fixed up real quick! just give him a minute to make the surgeon tool and whip up some new valves from scratch and you'll be restored like new! lol
He was a Navy Nuke (Electrician, IIRC). Many, many signatures in logbooks will destroy your handwriting very quickly.
I worked as a home health aide for a bit, was signing the logs about 120x a day (3 clients, 10-20meds each, 3x-4x a day). In less than a month, my signature went from something recognizable to a line.
Today I learned: a cigar has enough heat to light gunpowder
And you want a long cigar if you are using it as an ignition source.
Black powder has a shockingly low ignition temperature
AND CANCER!
I have read that a cigar is hot enough to light military time fuse for explosives
The old 20-12 boom! A quick, effective way of opening up a tight 12 gauge shotgun chamber for sure! Mark's right, it's all or nothing, one gauge or another. Be safe out there people. Rev. D.
Just a little toasty there on the arm.. lol great tip there with the 12 and 20 guage shells. Thanks again Mark, really appreciate your time and efforts here.
Education enlightens!
Mr. Novak your a great teacher! Thanks
You can think of calibers when doing quick/rough conversions of measurements...
.003" relates to .0762mm like .30" to 7.62mm just move the decimal point...
This only works if you are familiar with diameters
.177 - 4.5mm
.20 -5mm
.22 - 5.6mm
.277-.280 -7mm
.32 -8mm
.355" - 9mm
.40 - 10mm
etc.
The tendency of european calibers being given as diameter between lands (gauge diameter) and US calibers being given by groove or bullet diameter throws this off somewhat...
I would love to smoke a cigar and sip some single malt with Mark, however who wouldn't 🙂
Great video. Biggest takeaway for me was the 12ga and 20ga bit. How did I not know that?
Thanks for sharing your knowledge, always informative and entertaining.
I like building AKs and rpks. When I finally had to replace barrels is when I "learned" about head spacing.
It's a pleasure watching your videos--right to the point, and no BS. You're educating a hell of a lot of people-- THANK YOU!
nice info that I will forget in about a week.
Excellent! Thank you.
I knew about headspace, but when I was working as a woefully underpaid and over qualified gunsmith, a man brought me a .40 S&W pistol with a MOABO kaboom. He had been shooting his .40 and his 9mm at the same time and inadvertently loaded a 9mm round into the .40's mag. BOOM... BOOM... CLICK... TAP N RACK... KABLAMMO! The gun ended up being fine (after brand new barrel was installed) and the barrel didn't rupture but was so badly bulged that I had to put the whole seized up slide assembly on the mill to get the damn thing out.
Somehow that reminds me of the TAOFLEDERMAUS video where due to the ammo shortage someone was using spent .40S&W casings filling them with lead, putting a sholder on it and using them for the bullet for a .44 mag reload. A few seemed to wobble a bit, but it worked.. Imagine it's a bit rougher on your barrel, copper is quite a bit softer than brass. I'd of just used cast lead, but I guess they gotta make videos.
@@walkingcontradiction223 Yeah, I've seen that video. Cool stuff. But for it to be an analog to what I'm talking about (or what Mark was warning against in the video), they would have shoved a live .40 round in front of a live, normally loaded .44 mag. KABOOM, or MOABO (mother or all barrel obstructions).
@@krockpotbroccoli65 Yep, just said it reminded me of that for some reason... My brain goes off in weird tangents constantly.
I had a Daisy V/L back around 1969. It did not have a firing pin- it fired by compressed air being squirted through a hole in the front of the bolt. There wasn't any way to extract an unfired round, if it wouldn't shake out. Lots of lag time between pulling the trigger and actually firing. I got rid of it, but I still have a pile of ammo for it.
Once again I learn from you Mark. Thank you man, you're the best at what you do.
The king of valuable information. Thanks so much for giving so much. I enjoy your channel.
Fieldsports Channel did an episode on May 21 where they shot obstructed shotgun barrels. One of the obstructions they used was a 20 gage in a 12 gage.
It was indeed a pleasure hearing your headspace explanation. Thanks once again, Mark!
Great information, I could listen to your knowledge for hours, thank you.
Finally, an explanation I can understand! Nice, thanks.
My understanding is that the firing pin will push the entire cartridge forward until it stops, at which point the case is forced backward onto the bolt face while the remainder of the case is left to expand under >15k PSI against the chamber interior. In that sense, headspace is a dynamic event rather than a static number. While an attempt to capture microseconds of data in an environment characterized by lethal pressures is far more difficult than an effort to measure a distance with a micrometer or GO/NO-GO gauges, it does shed even more light on the extremely complex process of touching off a round.
I really appreciate the great explanation, which exceeded the already high standard set by your last effort. Thanks!
@Adam Schindler Your first sentence is correct, AFTER the trigger is pulled. Headspace is the measurement BEFORE the trigger is pulled. It is a static state (and measurement), not dynamic.
Yes. The issue that I'm trying to raise is that the issue of headspace matters when we're firing the cartridge, such that as soon as it really matters, headspace becomes far more complicated.
The Daisy caseless ammo does not utilize a firing pin at all. The propellent is ignited by compressed air, similar to a diesel engine.
Which is why it doesn't need exact headspace, yes.
I'm more amazed that Mark actually had some!
Thanks for the lesson sir.
Great job! Any newbie should be able to hold his own at the bar bs'ing headspace. Your next video on why headspace - should be very interesting. Now all ya need is extra time to make one. Thanks
Very clear, very usefull.
I learned two new things.
Mark you explained HeadSpace much clearer than they did in Gunners Mate school. BZ. But in my world I only worry about headspace when I’m reloading and sizing the case down (bumping the shoulder on a .223) by .002 on an already fired case. Getting a set of comparators makes life easier when reloading for a generous chamber like the .303 British
I actually tried to enlist as a GM in the early 80's, but the nav had other plans for me
This is the most well explained way to understand head spacing that I have ever heard. Fantastic explanation. There is one last way to headspace a round, in a manner of speaking but I consider it undesirable. A lot of bench rest guys load their bullets right to the point of jam and they are actually head spacing a round off the jammed bullet. But that is not a headspace from a case perspective. Excellent video!
Holleecow, Mark has some of that caseless ammo fer the Daisy firearm...
holy crap I did not know that about 20 gauge good to know!
Thank you for the info Mark. Great video very much appreciated.
I always thought headspace was what was between one's ears, thanks for the clarification Chief. ;-)
And don't load 300 blk in your 5.56 rifle.
And if you do that, you are either too drunk or too blind to be shooting anyway.
Very good way to blow up a bolt. And probably f up the barrel, too.
Thanks!! You made it simple and understandable.
Excellent! Thanks Mark.
Great Explanations ! Thank You !
As always love the wisdom you have!! I’m constantly watching your videos and others and reading books, buying another guy to see how it works, take it apart clean it fire it, I work on my friends guns nothing major no moving metal or anything just typically putting stuff together when I know they took it apart to clean it and can’t seem to get it back together!! I’m not smith and I don’t proclaim to be!! And if it paid better I would be in school so I could get a job as a smith right now!! But while I have a love for all things that go bang I got bills and a family to support so I have to be a part time gun lover. But just to gain the knowledge would be amazing!!
Perfect clarity! 👍
Well explained. Well understood. Thank you.
OUTSTANDING, as always.
How much per hour to stand in your shop quietly and take notes?
Thank you Mark. Very good presentation !!!! Excellent !!!!
Ricky from IBM, Ret
Outstanding! Great breakdown! Bad things happen if Headspace and Timing aren't set.
Best explanation I’ve ever seen of it.
Great review. I would love to hear your opinion about the importance of checking headspace on AR builds. I do check because I'm OCD. There are lots of these being put together and lately it's hard to single source parts like bolts and barrels. You buy what is available. Mil spec "should" go together properly but I have found combinations that are iffy.
He broke out the V/L ammo too!
Thank you!!
Good safety tip, I never realized the danger of mixing gauges.
Great video. Thank you for the information.
Excellent explanation!
Thanks Mark excellent as ever.
Your content is informative and interesting (for those of us that love to find out how these things work). I wish you every success. :)
My pop had a go/no go gauge for .30-06, presumably to ensure the 03-A3 was safe to fire. He nearly skinned me alive when I picked it up to ask about it, fearing I would drop it.
As a kid, the State of Michigan required me to take a hunters safety course before I could go afield armed with more than a wrist rocket. One of the things they went into great detail about was mixing 12 and 20 gauge.
Great video!! I would expect the primer in caseless ammo to headspace itself, and be the "seal" when the round is fired....
I had money on Mark setting off those 12 and 20 gauge with his cigar
Awesome! I had an idea about headspace but now I know about headspace.
Cheers
Mark, the Daisy caseless was fired by the heat of compressed air. It was basically a boosted air gun which ignited the propellent by the heat of the air coming out of the piston cylinder. There was a one way valve to stop back pressure getting into the piston side. It was basically a better engineered version of what we all did as kids, dripping model engine fuel into the piston. It does not have or need headspace in the conventional sense as nothing is hit or pinched and there is no firing pin as such.
The Dreyse and Chassepot are better examples of where headspace came from. I shoot both and getting it right so that the needle hits the primer is a Mk 1 PITA...
Can you say "In this particular case" when the ammo is caseless? ;)
Thank you that was awesome. Very clear , got it.
Thank you Mark!
Best headspace video ever!!
Thank you, great video!
Thanks, Mark. I think Ian had a former Marine armorer on when he shot a M2 to check this on the weapon.
Every M2 gunner in our squadron had a Headspace and Timing tool that became an inspectable part of their uniform. It was a bad day if they didn't have it on them while their M2 was out of the armory.
I can watch him all day.
I been shooting .45acp revolvers for a while. Cool post.
I've got a Smith that uses the moon clip (or half moon or 1/3 moon) It's fun to shoot too. With the moon clips you don't need a speed-loader.
Great explaination!