How shoulder bump affects seating depth

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[@BitsOfEternity]

Haven't started reloading yet - hoping to be able to get into it next year, and this is priceless. I can just imagine how much time and money I'd have wasted trying to figure out why I wasn't getting consistent groups.

[@benjaminhaas4634]

Another gem from Erik. It's so obvious once you explain it, but never would've thought through it on my own. Thanks Erik!

[@1rovin2]

These videos are incredibly helpful. I have gained so much more understanding of the various processes in reloading than I learned by just reading reloading manuals. Thank you, Eric.

[@concernedaussie1330]

Your a legend mate. I’ve learned so much this last weekend, but opened up so many new questions & ways to think about what’s going on .

[@rwhipple73]

Man, you have taught me so much in the handful of videos I've watched. You always break it down in a way that's easy to get.

[@AKGuru4774]

Can’t thank this man enough. Having been reloading for 20 years since age 5, I have found I have so much to learn. Can’t believe I’ve been doing it this long and no next to nothing in reloading. Thank you for rekindling my love for reloading man, it went from a chore of quick 1-1.25 inch shooters to less than .5 in rifles with 3-9 shot groups. Now I’m getting into long range with 308,338 lapua and 30-06. Can’t wait to learn more from your vids

[@hugoletkeman7049]

Thanks Eric! That was a great description!

[@genedavis759]

Had not focussed on that aspect before . Thanks for the Illustration .

[@rustycraig7562]

Great video but even more so, outstanding class Eric! Discovery learning sometimes sucks (20 years ago the hard way). Cost us a match but… please keep teaching us the great techniques.

[@carllangley1764]

Awesome Erik!! I'm definitely going to look you up and follow you!! Thank you very much for the information you are sharing with us!!!

[@steverando4154]

Mr Cortina you are very knowledgeable and have helped me understand precision handloading more than anyone. Thank You. I can't wait to apply these techniques when my rifle is done 👍

[@user-he5jp6bv1y]

Excellent presentation Erik, thank you.

[@sjohnson1776]

Very well presented topic Eric. Thanks! This also illustrates why using high quality bullets with consistent base to ogive dimension is so important. I just measured some (10 each) Sierra match 69 grain HPBT and some 55 grain Z-Max and they were within the +/- .0005" resolution of my caliper. I also measured some Berry's 55 grain and they varied by as much as .006" base to ogive! Not knocking Berry's...you get what you pay for which is why I use them as trainer rounds in my AR.

[@Longshothawk]

Glad your shop is coming along and glad your back sharing the knowledge.

[@robburton3255]

The ore I watch your videos, the more I realize what I don't/didn't know about reloading. Thank you!

[@ANGELCORRAL]

Good contribution. Thank you ... That's why I always measure each finished cartridge and if it is not in the correct dimension, I disassemble and correct ...

[@vdog4799]

Cool video. Bummer about the reloding stuff though. All the good guys are going to patreon. I don't do patreon unfortunately. Take care Eric! Your videos are great😁👍

[@thengine7]

"because they don't like it" is the reason he doesn't post non-patreon videos with that type of info.

[@russellmiller212]

No bad news about anything..only good news. Tube doesn't mind constructive content of any sort. Politics and the criticism of 'WOKISM' are another matter.

[@barryboyd7973]

Good stuff Erik. My reloading process includes annealing and pushing the shoulder back to a certain dimension and seating my bullets to a certain base to ogive dimension. I did not understand what happens if your shoulder bump is inconsistent or what you need to do to your searing depth to correct an inconsistent shoulder bump. Now I do, and it makes perfect sense. But, you are the first person I’ve seen to explain it and I find that very interesting. I’m thinking most people giving reloading advice do not really understand this basic concept, otherwise they would have made a point of explaining it just like you did.

[@wvlongshooter3912]

I was working on a reloading issue for two years. After my first patreon video, Erik’s content solved my issue that I was having. This was worth every penny ive spent on his patreon account. Great video!!!

[@repairfreak]

Awesome, thanks for explaining this. At first my dyslexic brain though at first you would seat the bullet less deep or longer from case head to Ogive if shoulder is bumped back further than desired. But then it popped in my head that by bumping the shoulder back it allows the case to move forward more before the shoulder hits, this would naturally then also move or push the bullet further into the rifling. And like you said to maintain your off the rifling distance consistent if you bump too far, split the distance of what bump you wanted and what you accidentally got, and then seat the bullet this much deeper into the neck, and then it’s just right. It’s easy to misunderstand some of these relationships and how they effect things. I feel like my blob of grey matter in my head-pan has just grown a couple thousandths of an inch from this video! Thanks Eric ✌️😎👍

[@frednurk4342]

Very impressive and well explained. Thanks for sharing you expertise

[@hickboy3067]

Makes sense to me, Keep them coming Eric!

[@BobSmith-zh6it]

I really had not thought about it that way either. But that works out. Thanks for the explanation. I have learned a lot from your videos.

[@russellmiller212]

Excellent observation; something to be aware of when neck sizing. Although most of my brass was of same manufacturer and lot including load component details) changes in seating depth was something I thought would occur anyway. Fortunately, there were no reductions in accuracy. In fact, the spreads may have tightened up. Consistency is preferred. The possibility of requiring the use of similar loads in other guns always makes FL desirable. After listening to your emphasis on the inconsistencies related to neck sizing, I plan to full length size all brass from now on, match rifle or field sporting rifle.

[@tinfoilsombrero1439]

Great video. Thanks for the lesson.

[@radmirmetalyogi5154]

Thank you Erik you are awesome!

[@orozcocris93]

Never thought of this and its great into! Thank you!

[@xforce708]

Ahh! Helps me a lot to understand and that I can do something with the ones I do occasionally bump too far. Thanks for all you do.

[@altonrowell7854]

That's really interesting information. I never thought of it. Man you know your stuff. Thanks again.

[@user-wz8bg4cj5c]

Thank you for this knowledge!

[@larrybowlin2908]

That was explained very well, and an eye opener for me, Thank You👍

[@slipknnnot]

Mr. Cortina thanks for your content sir.

[@2steedaq]

Thanks man. Glad I found you on YT.

[@newcreation2521]

Thanks for this video, very helpful!

[@jacobfranke3138]

Thank you Erik!

[@rokkinjohann]

I have zero competitive shooting experience, only 35 years of reloading 12 different bottleneck cartridges. I get 6 - 10 reloads of the same brass before work hardening of the neck splits during resizing, primer pockets go loose. I've been only neck sizing for decades; outside neck turning is my key to axial alignment. The crush fit of rechambering my brass into my rifles chamber is but a minor extra bit of pressure. There is no .002" to calculate, factor in, figure out, and phlilosophize about. I do work up a note card for each box of loads that includes these measurements: SAAMI OAL, max length in magazine, and length to touch lands. My loads are seated .020" off the lands if the max magazine length allows or .005" less than max mag length. I'd love to dial in a zero at 500yd and try the Blackjack with my .338 Lapua.

[@johnreynolds6499]

Thanks. I understand the concept.

[@davecunningham4726]

Awesome Erik. Thank you

[@michaelarthur5026]

Good good info, very appreciative. Thank you!

[@webbzgunnuts]

Appreciate the sharing of knowledge. I had always bumped mine back about .002 , but I also always pushed my bullets about .020 away from the lands. I wasn't chasing the lands, its just where that rifle grouped that load the best. I never thought about the firing pin pushing the brass forward, but I guess it would have to unless you seated the bullet into the lands, and we know thats a really bad idea. :)

[@chipsterb4946]

Thanks Erik! It took me a while for this to sink in. I think is the key is shoulder-to-ogive measurement. That is a set dimension of your chamber. Take your bullet comparator measurement from base-to-ogive, then subtract the base-to-shoulder measurement for a case… any case. Now you have a *fixed measurement of your chamber* from the shoulder to where bullet X hits the lands. Once you have this data point, it doesn’t matter if you are starting with new brass or brass you’ve fired twice in that rifle and bumped the shoulder back .002” or .005”. If the shoulder-to-ogive measurement stays the same, you should be good to go. P.S. I understand that this measurement will drift over time as your throat depth extends.

[@meadows28572]

Thanks Eric!

[@graynotescartridgebox]

Good visualization and explanation. It’s a topic hard to explain and I’ve wanted to explain it to people and it just never clicked with them. I’ll just share your video.

[@ramsaycountry1177]

I've never thought of it this way, but it definitely makes sense. Thanks Erik 👍👍

[@JorsMalan]

Great explanation, thanks.

[@aaronarcher2356]

Excellent way to explain this

[@DenverLoveless]

This makes great sense! Thank you. I don't compete. Just recreational and hunting stuff. This info will come in Very handy with the lee dies I have. The bump is not consistent. 2, 3, even 4 thou difference from start to finish. Again thank you.

[@scottbutler2761]

Glad to see you are ok Erik

[@tyler6147]

Welcome back Erik!

[@MrBbracken]

Very cool video. Consistency is king! Get it right, then keep it right. Only make adjustments when the need is demonstrated or required.

[@blackbird567kh7]

I love videos like this!! More please!

[@caseybritton2616]

Brilliant thanks for the content.

[@TheSpeza88]

spot on , couldn't be clearer . something i never thought of TBH

[@paulgandy8400]

Muchisimo Gracias Erik

[@bennettdavid904]

Thank you! This makes a ton of sense.

[@tymarkham3931]

Wowwwwwwww that was some great information. Thanks, brother 🙏

[@mamiz69]

Makes sense indeed!! Thanks Erik! :D

[@judybuss9350]

Thanks Erik very informative

[@danielbuss8788]

Got it Erik. Thank You!

[@mikebell7324]

Thanks Eric

[@michaelmcgowan9518]

I appreciate the way you explain what I'm seeing, but I didn't understand. THANKS

[@charlescowan1418]

Hey Eric, knowing is half the battle…, thanks for sharing your knowledge brother

[@358Magnum]

Good explaining! Consistance is the leadword.

[@PassionforRifles]

That was very well explained, it all makes sence. No more neck sizing, even it is faster, but the accuracy must be the main key, no quantity over quality.

[@thomass8362]

Passion For Rifles - Just like with bad drugs, just say NO to neck sizing! Believe me bro the withdraw isn't that bad. :)

[@JohnSmith-fi2gu]

Thanks Erik

[@kennethtephabock5634]

Awesome video Erik

[@patricks7622]

Thanks for that, have fun.

[@michaelarmstrong3246]

Great explanation

[@savagereloader6699]

Good piece of the puzzle people overlook and hopefully gets them thinking of brass manufacturer differences and even variance between lots and composition as well projectiles.

[@laurabrock1249]

Just thinking after trying to absorb your knowledge. In sizing once fired 30-338 Winchester brass would it be best to bump the shoulder say 2-3 thousandths and just keep it consistent while it headspaces on the belt by design?

[@savagereloader6699]

@@laurabrock1249 other people may have their own opinions on this but as I see it I would absolutely minimal FL size in a bowl action to 2-3 thousandth shoulder bump. Whether headspacing on the belt or not, the brass is still going to expand to obturate the chamber and their is benefits to be gained from less expansion of the case exlained by Eric's videos.

[@rodocs7]

Such a good video!!! Thank you!!! I have .23 5 shot groups now because of your videos!!! Much appreciated

[@Russell-1]

Anthony - is 0.23” your average group size & if so how many groups were used to determine the average?

[@planeiron241]

@@Russell-1 in the .2s is great good shooting now down to .1s and then .0s I have shot a couple .0 groups like 2 my whole life my smallest is .087

[@mossranchoutdoors7249]

Great explanation!

[@hank3152]

Makes sense and easily understood

[@Snedstige]

Great video!

[@keokio7]

im learning so much thx

[@timprice6265]

Awesome example of above-average intelligence my brother and I have been shooting and doing Precision reloading all of our lives. This example a shoulder bump could possibly be some of our issues we've been having lately. Makes perfect sense. Thank you. Will forward this to my brother.

[@toddcumberland132]

Taking care of yourself and your business is nothing to be sorry for and you are not "hanging us" out to dry. Keep up your work and doing what it is that you need to be doing. Keep on Keeping on.

[@birddog7492]

I love watching this guy he knows his stuff.

[@BR-hr1kx]

Erik, you literally saved my match Sunday. I accidentally bumped 6 thou on everything I was testing today. After today, I have no time to test before the match. I was able to shoulder bump 2 thou when I got home now and seat the bullets 4 thou deeper than the long end of my seating depth node. THANK YOU

[@usa5865]

You will not believe the arguments I've been getting into in my reloading group because of you lol. I've been trying and testing what you do and having good results so I've been posting it. Man do people get mad when you show them full size works better. Then I posted an annealing video that just barely got the neck glowing and they lost their minds so I posted your 20 second test. I can't wait to piss people off with this. Your advice works man, thanks

[@ErikCortina]

😂

[@tinfoilsombrero1439]

Ive never understood people who become defensive over their reloading techniques. If there is a person out there who does it the exact same way since they began, they are ignorant. I’m always looking to improve. Perhaps, that’s it; not everyone has the gift of critical thought and is able to challenge their own beliefs. Whatever....I choose learning.

[@slipknnnot]

I was debating if I should get a $30 tempilaq bottle or not and then I watched the Erik Cortina video that pretty much confirmed that I can Ugga Dugga it by watching it glow and it works flawlessly

[@Dfleuryoutdoors]

Learn something new everyday. I would have never even thought about this.

[@jessewerner4067]

Great video and so true! I normally check all of my sized case shoulder datums and sort by length...although it generally varies very little. I adjust seating depth accordingly so all bullets have the same jump. Nowwwww....I recently bought the Accuracy One Seating Depth Comparator. What a time saver! This eliminates the need for any sorting as it measures shoulder to bullet ogive which is THE ONLY MEASUREMENT THAT MATTERS ANYWAY! Wish I would have bought it sooner

[@danielmaine45]

I think that depends on the cartridge...

[@jessewerner4067]

@@danielmaine45 the process you mean? It has nothing to do with cartridge unless we're talking semi auto rifles or straight walled cases 🤷‍♀️

[@danielmaine45]

@@jessewerner4067 Well ....I was looking at it from a rimmed cartridge vs a semi rimmed bottle neck cartridge (like he shows). Because the two would head space from different datum points the firing pin moving the cartridge could really change things...when the round goes off, which is something I have noticed when shooting 30-30 cartridges for example. Not looking to start an argument or anything. I fully admit I'm not an expert, just a guy who enjoys reloading his rifles for better accuracy and cost savings. Maybe Eric could charm in and provide some insight some time... Happy Independence Day🎉 (assuming your USA)

[@danielmaine45]

@@jessewerner4067 sorry...I just saw the part of your post about straight walled and rimmed! Thanks!

[@anthonyross9276]

Well done sir! You are good at explaining these things. I come from a family of farmers,machinists,and fabricators. We are also pretty good mechanics by necessity but some of this reloading stuff confuses me at times!

[@ErikCortina]

I grew up ranching and baling hay, some days I miss it.

[@anthonyross9276]

@@ErikCortina for sure. My day job keeps me away from the farm more than i like.

[@jeffmorrow1957]

Thank you Eric it makes perfect sense but I just never thaught of it

[@betocool78]

Ya se te extrañaba amigo. Un abrazo

[@intellectualiconoclasm3264]

It makes perfect sense. In machining terms, your case becomes a reference. If it's out a few thou than the product, your accuracy, won't have a common reference. Once that calibrated surface is gone, especially in a worn weapon, your ratios inside the chamber and barrel change. That can change your pressures, burn rates, and everything else. Thanks for making it so simple. Basic math and the white board of knowledge are powerful tools lol.

[@nicsu2128]

This is perfect! I just prepped som brass yesterday and bumped a few too far back. I can just adjust the ogive out the same amount I pushed the shoulder back too far by.

[@jamesmiller360]

Good info, thanks.

[@miguelperaza6615]

I think that for an amateur reloader ? The two most impormant basic rules are : 1 - size your brass according to your chamber correctly and precisely!! 2 - seat your bullet according to Erik's system of jam ! And lastly find the right amount of powder that groups better . There you have it . Later on we all can go into ballistics theory 🤭

[@v10squirrel]

Thank you for sharing

[@patrickcook9142]

Thank you Eric, we always said KISS @ UPS. Keep it simple stupid, worked for me for 30yr. Thank you Sir.

[@RealHank1791]

Great info.

[@briananderson2780]

Makes perfect sense. Thanks!

[@nilsfernquist2387]

Firing pin driving case forward but doesn't the ignition drive it back to meet bolt face before bullet leaving? Guess km wrong but that would suggest jump stays same regardless of shoulder bump?

Thx for this explaination

[@katashi222]

Bingo!!! Houston, the eagle has landed!!! I was reloading and now I understand the whole process. Therefore I do not neck size, so I keep my seating depth consistent!!!💯🤙👍

[@extremepyro624]

I have this little saying since I've starting getting into precision shooting. Precision shootings a little like the lottery. Think about all the variables for a shot. Let's start with this video. Shoulder bump, seating depth, neck tension, brass used, powder ( all of them that are options for that load ) primers ( all of them that are options for that load) , Bullets ( now there's a list ) , velocity, trueing velocity and Bc , wind , getting dope perfect, barrel tuner ( ordered mine yesterday) , Gun ( dont even know where to start with this one) now let's put the human in charge of it all and see how she sails lol Great to have Erik helping with a hobby that's got one heck of a pile of stuff to consider.

[@John-uo1qf]

Shooting still beats golf any day! :)

[@extremepyro624]

@Discerning yes it does !!!:-)

[@paulscharf8704]

Great video. Never considered primer strikes effect on seating depth.

[@juliogonzales9217]

Pressure signs, increased seating depth and no more flat primers even with increased charge. Totally get it now. Thank you

[@DRUNKENZANDER]

So if I understood correctly... Example: You shoot cartridge. Without sizing the brass you insert a bullet and measure the maximum overall cartridge length with for example Hornady COL cauge to know the maximum seating depth of the bullet on your specific firearm. Then you want the bullet to be for example .050" off from the lands. You measure base to ogive length .050" shorter than the max base to ogive what you got by measuring the length with COL cauge and not sized fired brass. But the brass prepared for loading is full sized and is going to be pushed back .002" from shoulder. That way the brass is going to travel in the chamber .002" as the firing pin pushes it forward to ignite. So if I got it right the actual travel for the bullet to lands is actually .048" and not .050" ? That way you would need to PLUS not minus the shoulder bump for the pursued dimension. Thanks for anybody to leave a clarifying comment!

[@fishlife1013]

I was wondering if this effected the seating depth this has been very very very helpful in validating my theory and now I can reload with a little more confidence its been so hard because the group that I shoot with neck sizes and there all old school