THANK YOU!!!! What a concise, clear and informative piece!!!! Thank you for taking the time to share your knowledge and experience.

Thank you, thank you, thank you! I am an old guy, who is just now looking into reloading and this video has been extremely beneficial in teaching me the purpose and need for Hornady Headspace gauages. Again, thank you for making this video and for leaving up on KZfaq.

Thank you for clear & concise explanations. Your channel is one of my favorites for reloading.

I'm a new reloader and I've been scratching my head for months trying to find out the purpose for the Hornady "Headspace Gauge". Finally I got it! Its not a headspace gauge at all. Its a case comparator. I now know what the benefits are (better accuracy, consistency and longer case life) and how to take advantage of its use. Excellent.

I'm new to reloading. Excellent tutorial. Thank you. Hornady makes an OAL comparator, a bullet comparator, this headspace gauge comparator (ie, base to shoulder comparator), and possibly also a case space/head length gauge (Lyman); which you mention towards the end. They all serve different purposes!

Just found your site. Great video. Excellent instruction! Sincere thanks.

Even though it is two years old it helped me 100%. If you guys have not bought his program. It is the best program for the money 10x over.

Thanks again. I just commented on your other video about COAL. I have recently purchased both comparator & headspace sets.

Just found this. SUPER helpful. Thank you!

thank you for your videos, especially for us novice guys much appreciated.

Excellent andvery informative. thank you:)

Thank you brother great instruction video!

Hornady Loader, Forgot to mention how much I enjoy your videos and find them very informative. They have helped me immensely. Thank You

I have recently purchased a 375 H&H Magnum rifle with the intention of hunting cape buffalo. Based on my experience with their ELD-X ammunition in .30-06, with which I hunted plains game, I plan to use Hornady's latest dangerous game round, the 300 gr DGX. Unfortunately, this ammunition is virtually unavailable, but the DGX bullets, .375 cases, and the recommended powder and primers are available. I am naturally interested in building the most accurate, high performance ammunition possible. For that reason, for the first time in my several years of reloading, I am paying attention to headspace and OAL. I found this video and the one on Hornady's Overall Length Gauge and Bullet Comparator extremely valuable in refining my reloading processes to include these key measurements. Of particular value was the information on selecting the correct bushing for the Headspace Gauge and the Information on the OAL video on calculating the True OAL. The videos clearly show how to use these tools, and I have played them through, while I make measurements. One thing I have discovered is that there are variations in both the Headspace and OAL measurements that I am making. My initial measurement of OAL for my rifle and the 300 gr DGX bullet varied from + 0.038" to - 0.014" from the average of 3.211 over nine readings. Headspace on the unfired cartridges varied from 2.509" to 2.522" around an average of 2.515". I don't know if these are significant or not, but since they were the first ones I made, I will go for another set to see if accuracy improves with experience. Anyway, these were great videos from the identification of the tools needed to how to use them. Thank you for sharing your experience.

Very informative. Thanks for making this video.

Great vid, well explained !

Well done video! Was looking at this product online and wondering how and why to use it. thanks!

Good video. Excellent information. 👍

+mfgunit Yes, you do. It's common practice to bump the shoulder back by 0.002 to 0.003" for cartridges that will be fired in a bolt action rifle, and 0.003 to 0.005" in a semi-auto rifle.. This is done to insure that the round will chamber reliably. There are reloaders who do not bump the shoulder back on their fire-formed cases every time, especially on cartridges for a bolt action rifle since they have control of the chambering process. But consider a semi-auto rifle like an AR-15. As the bolt carrier moves forward, the bolt is rotated so that the lugs on the bolt engage the corresponding lugs of the chamber to lock it in place (goes into battery). If you have ZERO tolerance in your headspacing, any deviation whatsoever in the length of the case may cause the bolt to hang up on the chamber lugs and fail to lock. I've also been in competitions where we fire hundreds of rounds with little or no time to get in there and clean out any buildup that might collect inside the chamber. This would cause the cartridge to hang back just a little, causing a failure to go into battery. By measuring the headspace of your fire formed cases, you can use that measurement to bump the shoulder back and give it a little tolerance so that this doesn't happen. There are other factors as well, for example if your rifle has never been blueprinted, the bolt face may be off by 0.001" or so and with ZERO tolerance, you could experience a failure to go into battery. Experiment with your rifle, if you find that bumping the shoulder back isn't necessary, then by all means go for it. As for me, I prefer to add a little tolerance so I'm not fiddling with my rifle while seconds tick by during a competition. Thanks for watching!

Good job, I’m an ex toolmaker looking to get started in precision loading I understand everything you said good job explaining it.

Thank you for your very informative videos amazing knowledge i will start reloading very soon but I'm watching all your videos before hand thanks again will like to talk to you soon for some other tips

Thanks Hornady Loader! Great explanation on the use of this tool and why it is a useful one. I'll be sharing this video with friends, as I've attempted to explain this, but you've done a much better job.

Thanks for this video, very informative and easy to understand.

Great information. Thanks for the video.

Wow his videos where ahead of the time!

Дякую діду! Дуже корисно!

Thank you for the advice

Thank you sir for the very clear instructions. I just received my comparator and was scratching my head since it didn't seem to be measuring the actual headspace. The instructions on the package are not clear and most online reviews I've read made no mention of this being a headspace comparator rather than a true headspace gauge.

Finally, a clear explanation.

Thanks for the video

Great videos

Great video.

I think you were talking about work hardening in your brass from firing to resizing. Would you consider annealing your brass? It would be more work, but, if you are concerned about the life of your brass and keeping it safe from splitting at the neck, annealing may be something to consider. And, thank you for a great explanation and demonstration on the Hornady headspace tools.

could you take the measurement given by the head space comparator, find the difference between min/max saami spec and use that difference with the measurement obtained from the hornady tool?

Great videos I'm going through every one...did you put the comparator on the wrong arm of the caliber you said to put it on the travelling arm ..you have put it on the stationary arm ..just a small point...what do you think of the Hornady neck sizing die for my 6.5 Creedmoor....

Great video as always. I have a question about the Lyman headspace gauge that you put your UNFIRED round into and it fit perfect. I did the same thing with a brand new 6.5 Creedmoor Hornady 140 gr ELD Match round, and it fit perfect as I expected. I put a ONCE fired cartridge in the Lyman headspace gauge and it got all the way down to about what I would call the case head (approx. 1/8" away from all the way in). Is this normal for a once fired cartridge to not fit in the gauge and need resized already, or is it because the Lyman gauge is going off Saami specs and it still may be ok for MY rifle? I also bought the Hornady headspace gauge but have not tried it yet. Also, I failed to mention that I am shooting it out of a Bergara bolt action rifle. Thank you and look forward to hearing from you.

You rock...

Do you have a video on the Hornaday Case Prep Center? Thanks

I got a big question. The difference between my fired 308 out of my MVP-LR using PPU 308 Match HPBT is no different that the UNFIRED case. They both set at 1.63. I am using the "D" Headspace. The FIRED case has not been resized. Is this possible??

Horn..loader, I am switching from 22LR to 22 Hornet and looking for a Hornady Headspace bushing for this sweet little varmint round. I can't fine one, any suggestions ? Thanks, Ed

Have you reloaded any of the new Hornady A-Tip Match bullets yet and if so could you let me know what episode it was. Thanks JR

Is it OK to set the head space of my cartridge above SAAMI standards if it works in my gun?

Well explained but have a question.Do u full size the case first then bump the shoulder and then trim .What would be the correct steps.Very new to this hoping to do it correctly.Help would be appeciated .Thanks

My comparator body only has one hole in it. I bought a headspace bushing separately ... is this correct ?

I just measured 5 rounds of factory white box Walmart cheap federal ammo in .308 and found that it averaged 1.619 with my gauge and after firing cases were only 1.621 - 1.622, not bad, this is why I got sub moa group with it. What I don't understand is this is not max chamber expansion though as I was able to fit cases as much as 1.627", only at 1.630+ it wouldn't fit. This gun is H&R handi rifle single shot and has tight chamber, I have to use RCBS small base die for brass I pickup that's not mine. In order not to oversize, I backed up the die 1 turn and now it sizes .469 at the base diameter while I believe the max is .470 where as if I had the die touching the shell plate it would size down to .466. This setup causes the neck to size beyond the headspace I need so I have to size it again with Lee die to push the shoulders back, I am thinking of reaming or boring out the neck in RCBS die so it only sizes body and than I can use Lee collet sizer or properly setup FL die to size neck and bump shoulders if needed.

What Hornaday insert do you use for 357 sig??

After you measure all your cases for proper head space do you trim your brass to specs?

So you measured 3 pieces of fired brass got the same measurement. When I measured my fired brass, I got all different measurements. The brass was all hornedy once fired. So what measurement do I go by, do I take an average?

If your brass likes to expand 6/1000, would you cuase a problem when you only give 2/1000 room for expansion? The only question I have is what does brass length has to do with head space. Head space measures from the brass rim to the shoulder. I just don't see how this is going to help accuracy.

Now for part 2 when ya bump it back. Thumbs up

Thanks a bunch; very helpful. Best wishes. J.

Thank you for this very informative video. Will I need the inserts for the comparator body to do this procedure or just the body itself?

Is it normal for them all to be the same size after fire forming? After shooting in my garand, none of them are the same size.

What I don't understand is if you fire-form your brass to be fired with the same rifle, do you even NEED to be concerned about headspace?

Do you have a video on neck sizing? I would also like to know your take on neck sizing cases to be fired in a semi-auto (AR) rifle vs. bolt action. I have been told by some, not to use neck sizing for semi auto.. Tks doc

I don't understand the purpose of the go no go gauge. I can see your neck poking out if you need a trim, but the rim of the cartridge isn't going poke out of the top is it? Case separation.

Hello again, I'm understanding reloading a bit more and really enjoy your videos. I'm looking at getting another tool for reloading and I'm thinking of this hornady headspace gauge or le Wilson case length headspace gage for for my .308 win and 6.5 creedmoor which tool do you think will better improve my reloading? Thanks again please continue to making these very useful videos.

Okay what size for 30- 378 and 338-378 what should I do guys

Can you please do a video that shows how to use the rcbs precision mic properly?

A+++++++++++++++++++++++++++++++++++. Thank you for all.

Great videos I'm having some problems trying to learn to shoulder bump, I have some once fired Winchester brass that I shot from my rifle and it has the same headspace as the ones that haven't been fired just wondering if this is normal. Also I have some old 308 brass that I'm trying to practice headspace bump but I'm getting no change in headspace readings until I'm pretty much full length sizing and then the reading actually gets longer for example from 1.620 to 1.640 how does this make sense

Hornady Loader, Bob Austin here, I would like to pick your brain if you don't mind. I am reloading for a .243 Win. and with the Hornady headspace gauge fireformed cases have a headspace of 1.622 inches. I have full length resized them using the Redding competition shell holder set to a headspace of 1.622 in. and they chamber easily into the rifle. Should I still bump the shoulder back another .002 in. or is it Ok to leave them at 1.622 in.

Hornady Loader, Bob Austin here again. I am reloading 7 mm Rem.Mag. Cartridges and using the Hornady headspace gauge, it tells me they are expanding .015 when fire formed. I understand that a belted magnum head spaces from the belt and not the case shoulder. Am I getting an accurate reading or maybe the Hornady headspace gauge does not work on belted cases. I would like to be able to bump the shoulder back .002 or .003. I don't think the Redding competition she'll holders will work. Can I just back the full length resizing out to do that?

Traveling arm of the caliper? Why does it make a difference? Which is the "traveling arm?"

How are you going to move the shoulder back 6/1000 if you set it back only 2/1000? Do mean mean you will do this three times to go back 6/1000?

love your videos, but am I little confused. should I measure a fired case or a virgin case ?? to determine correct headspace bushing to use

Hello I have looked ever place I could think of for Info=. Maybe you can help me I even emailed Hodgdon they have not mailed me as of now! Is there a code for what powder is used- let me explain is there a code for what kind of powder, extruded powder, ball powder, flack powder. I heard Hodgon H322 is a ball powder, I would like to us a fast burning powder I have heard that H322 is a fast burning, ball powder, good powder to us with a 1-12 twist with a V-Max 40gr bullet out of a 223. The powder dispenser I us works best with all but the extruded.

Where can you buy the Base Anvil? Cabelas & Hornady does not list it.

is the headspace gauge the same tool as the bullet comparator

Where can I get a step by step procedure for the CORRECT way to shoulder bump. I have taken instruction from different reloader and they all tell me something different. Im not having much luck with any of them. thanks for any info...Doc

great vid! Question. when comparing headspace from your fire formed brass vs a resized case from a full resizing die with this gauge setup what would be a safe limit in thousands for operating in a bolt gun? According to my wilson gauges it seems like I'm just under sammi. Very borderline. I ordered these hornady gauges to be sure I'm in safe operating conditions.

Help me. Does the headspace figures mean anything to someone firing a 45 70 cartridge and if so how?

Thanks for the video, I just subscribed! I tore my hair out yesterday trying to measure a fire formed case in my LE Wilson case gage (30/06) and cases I had already sized after setting my die up to "cam over". I was using the depth mic on my calipers and I don't think it was very consistent. This tool appears to offer the same customization as the bullet comparator and OAL gauge correct? Thereby, customizing the headspace for your particular gun's chamber? I am going to order one of these gauges, I shoudl be able to measure a fire formed case then determine where I want to set my die correct? Now with a bolt gun I have rad that .002 - .003 variance is what I want to strive for. Does that mean I set my unfired and unloaded case to a value .002 - .003 below what I measured off the fired case? In your example, you measured a fired case at 1.618 and determined that you wanted to set your die to resize cases to 1.616. So you essentially turn the die down in small increments until you reach that value right? Lastly, can you work the same case multiple times until you achieve this measurement? I was trying that but I think the inconsistency of the depth mic on my caliper was working against me. Sorry for the lengthy multi-question here. Thanks for any help you can provide!

Hi think you fitted comparator to wrong part of caliper should be other way round but enjoyed video...

Well, apparently the owner of this channel died a couple of years ago. His last video was 4 years ago.

That centerline you’re trying to figure out is called the datum and it is a S.A.A.M.I. value thats listed for each caliber online at salami.org

when i went to school travailing ment moving, stationary ment nonmoving or stationary

Hornady Loader, Bob Austin here again. I just read your response to mfgunit and it lookes like you are answering my question. If that is the case just ignore me and I will try to do a better job of reading the previous posts and not asking the same question over again. Sorry and Thanks.

+Richard Herrera That's great Richard! The best comment I can get is hearing that someone learned something useful from one of my videos! You've made my day!

i am sorry to have to correct u, but heaspace is a tollerance in the gun it self , and not the dimensions of ammo, it is related but not the same ! it is didacticly wrong to use ammo to talk about gun dimensions . ( englisch is not my native language ) i used to work in a NATO test centre and measuring guns was my proffession.

Oh my goodness we are talking 2 thousand of an inch..or even 5 thousands..what a waste of time for hunting rifles but a great video presentation.

This video sucked. I have been reloading for 40 years and if I had seen this before I started, I never would have become a reloader.

I don’t do that anymore I just trim the case length if it gets too long