AMP Bullet Seating Press (1000yd Chamfer Testing) 

I feel like this can solve a lot of questions but then create twice as many

I've watched these AMP press bullet seating videos from several youtubers and have a different question. Most, if not all, of us who anneal cases do so before we resize and load the case. A video by AMP that answers the question about 'what if the same case gets annealed twice' clearly shows that every part of the sizing and seating process adds to case hardness. I'm now thinking about changing my process to move annealing AFTER resizing so that the only thing to do is prime, charge and seat a bullet. I wonder if the AMP press will show more consistent seating pressure on cases that have been processed in that manner. I intend to do some testing with that order and hope that you will be intrigued enough to test this with the AMP press. Thanks for your videos.

The angle of the chamfer is going to give a difference in this chart as well

Good morning, one test that I would like to see, is when you fully seat to length, and one where you seat 50 thou long, day later you seat to final length. Great info John, thanks

You're actually saving people a lot of money John as your analysis and results are showing people whether their reloading process is good or not.

Try brushing the inside of the neck with a lapping compound. Then after that us your expander mandrel to size. I use a drill and a worn out nylon brush with a cotton cloth patch to hold the lapping compound

Id say your dealing with stiction. How about putting some lube on the bullet or in the neck. See if it flattens out the curves at all. Looking at the inside of the case looks like some spallin/dragging in the case necks too.

Great test. In my mind i would think that the results are more of result of chamber sealing during the shot start time of the process. I would think that the heavy chamfer will allow the case mouth to seal very quickly and easy compared to the other scenarios. Thanks for the great info.

Wonder what it would be like if you brush then run mandrel in neck after chamfer to make sure no raised edge is made by blade.

the matching surfaces of the inner chamfer and the boattail seems an interesting area to look at : does it make sense to extract the one bullet that caused this higher hump and measure the profile of its boattail ? and compare to others . It could lead to designing a tool to check for boattail shape . Swaged bullets should all be the same if thay come frome the same base die , except the one that was made with a slightly irregular jacket that was more or less elastic than others . In short range BR , our top competitors who make their own bullets have jacket checking tools : some lots are outstandingly regular and generally produce "magic" bullets .

Great test John, I’m definitely loving these case prep test. The results are very interesting and surprising. Keep up the good work Johnny loving it 👍

I’m fascinated by this new tool and have high hopes for new discoveries in accuracy. Thanks for sharing.

I have noticed the need to heavy chamfer when using all copper constructed bullets with the rider bands. I have also noticed an increase in accuracy when doing both outside and inside deburing.

Hi. Enjoying the channel, thanks. I have found annealing after sizing/trimming/brushing/expander to have consistently less vertical. I’m using arbor press with force pack. I also use dry lube on case for expanding as well as the bullets. Thanks

This was great . Looking forward to the next step. Looked like 4 in the X ring at a thousand yards with the deep chamfered edge. Good shooting from the test. Hopefully you will work it out to the best way to load.

I would guess that the initial pressure rise is the case resisting the bullet entry, not use of the distance scale at the bottom, but it appears that the pressure drops once the bullet has more contact area and the case mouth starts to open. As the bullet enters the mouth more and more the additional surface (friction) area in contact with the case mouth causes the pressure to continue to rise. Do you use any type of lube, like a graphite? That may give you more consistency after the initial hump. Also, the less chamfer may be causing scratches in the bullet and increasing the resistance. Great testing. One thing I have learned from working in labs, when you change something, you only change one thing at a time.

John, do you neck turn? If so, do you Mike the thickness of the neck to eliminate the possibility of different tension? Just a thought, as I know that at one time benchrest shooters were adamant about neck tension. Just “threw on” ? Yea, right…….

I have been into long range shooting the past 4 years, but I'm baby steps into reloading and have a few questions. As a data analyst I find this data fascinating and would like to know more. How was the brass prepped? New brass? Annealing? Chamfer tools used for consistency? I ask this as I am developing a round to shoot at 1000 meters in .308win. If I'm not mistaken the P value in the graph is the bullet seating pressure in psi, correct? I see a very wide discrepancy between some rounds being loaded and wonder if it's due to the tools and technique used to prep and chamfer the brass before bullet seating. I can shoot 3 out of 5 at 800 meters within a 20x30sm (10x12in) with factory ammo (Hornady 168grn ELDM) , but have just recently prepped 100 brand new Lapua cases by hand, chamfering and deburring with a hand-tool (about 3 hours of work by hand, remembering how many turns I make @ each brass). I am FL sizing the brass and WISH to be able to hit a clay pigeon ~5in (12cm) @ 1000 meters. Would it matter if the chamfering and deburring operation is done on an expensive tool, 3-way operation tool or similar, or it would be difficult to account for variations / accuracy of said tool, given powder rates variations and other variables? I'm curious to find out do I need several more monthly wages into measuring equipment or just call it a day with factory ammo @ 800 meters? Here in Europe everything is expensive, and paying 2 EUR per round and thousands more into supplies almost diminishes the idea of reloading. But my inner nerd won't shut up.

Maybe matching the chamfer angle to the boat tail angle of the bullet could be something to look for, for having perfect contact initiation.... Just thinking out loud here.

Great video Sir, Very informative and one of my big questions. I use a lite non aggressive chamfer and deburr. It seems to be working great for me, but there is always that question at hand.

That is fantastic information I will definitely use this. Thank you

We need to see bullet extraction numbers. Going in is friction grain one way. Reversing is another. Jmho

Thank you for all the great info. So do you chamfer at 45° because I read some where to chamfer at a steeper angle?

Thank you for sharing your research.

Hi John, Not sure my comment is significant or not and is not relevant to this video. However I wanted share a concern relative to bullet manufacturer’s published data. Specifically, the center of gravity of the bullet (projectile) relative to the length of the projectile? Do they have data that can relate C.G. Location relative to the axial length of the projectile? Is the C.G. located in the center of the caliber bearing surface distance or is it skewed towards the nose or tail of the projectile? Is it important?

Was watching Quarter Minute Magnums and after trimming a bench rest shooter taught him to deburr using steel wool… would be an interesting test…

Hi John, Erik sent me to subscribe, but I am already subscribed. You'll get to 10,000 very soon. Keep up the good work!

Thanks for the video. Good information.

Great video John. With that said, I have to turn my TV volume to 70 in order to hear you. I'm usually at 15-20 normally. There's a way to turn it up in upload settings. Maybe turn your level up a couple notches please. Cheers!

Nice

Sent here by Eric

Do you chamfer even if the case doesn't require trimming? I have been as it assists bullet seating.

Nice job John. Very interesting to say the least. I assume that all bullets had the same seating depth. Are you going to leave that seating depth or change it. I would wonder if that would be the next move?

Have you tried running a nylon brush through the necks before seating? Supposedly the AMP guys saw a big improvement on seating pressure uniformity by brushing the necks before loading

The formula for friction has no component for surface area. Surface area does not matter to friction.

Just sub’d. Between you and Erik, I think I’ll have a chance at getting dialed in.

Great video John, Did you ever get the Auto Run to work? If so, what did you do to make it work?

Hey... do you use dry lube like neck sizing graphite when seating bullets? Has this been tested?

Are you cleaning your brass a second time . After sizing before reloading

When using VLD bullets

Did you chamfer the mouth before or after using the expander ?

Have you said how much neck tension?

Eric sent me

Are you using a vld chamfer tool ?