Danged Pinholes

[Ian]

One thing at a time. Deal with hourglassed bullets, alloy blends, and casting nuances another time.

Try partial sizing your brass to give you about a .002" grip on the bullet, i.e. about .377-.378" or so, something like that. Just use your expander to bell the case enough to get your bullets started without shaving any lead. No point in FL sizing and then stretching them back out with an expander, that just overworks your brass and causes the case to fit too loose in the chamber.

Figure out your jam length and subtract .020" or so (just an arbitrary number to try) and set your seating die so the bullet sits about .020" off the ball seat/funnel/forcing cone or whatever you want to call it.

Load up a few and hit the range.

 

[fiver]

just an fyi.
I size to 379 for my 38 cal type rifles.

 

[Chris C]

I loaded up a dummy round. Full-length sized the case and seated a .377" bullet. Just behind my .394" "sudo" crimp, it measures .392". So I most definitely was giving you incorrect measurements. Sorry 'bout dat!

My neck expander is .375", so how should I achieve a .378" size............by controlling the depth of the sizing die?

COL is 2.540", so I'll back it up to 2.520" and load up some. (but why not have the bullet touching the lands?)

Someone mentioned Unique was too high pressured for what I'm doing and suggested RL7 and 2400. I don't have any RL7 or even access to any. I've less than a pound of 2400 and can't seem to find any more, so I'm saving that. I do have some IMR4198 and it shows as an equivalent to RL7. Also have IMR3031 which is shown as the "most accurate" in the Lyman Cast Bullet Handbook. They show 26 gr to start. Any suggestions?

 

[fiver]

the die is tapered so keep backing the size die out..
3031 or 4198 will work.

 

[Chris C]

Okay, thanks, fiver.

Question: 4198 shows 14,300 CUP and 3031 shows 23,300 CUP. Way back, buried in this thread, someone mentioned I need to keep the pressure around 15K. So would I be better of the the 4198...........or would either work pretty much the same?

 

[Ian]

I mentioned staying around 15K with the alloy you were casting your bullets from at the beginning of the thread...for now. It's a starting point.

4198 will be fine, but it might like the bullet seated closer to the lands. Unique will be fine too but you need to NOT jam the bullet into the throat because this sharp pressure spike will tend to rivet the base. Also, if you choose to continue with Unique, drop back to 7-8 grains and keep it low so you don't break the sound barrier. The bullet needs a head start at the throat if you use fast powders like Unique. Starting from a dead stop against a restriction peaks the pressure right when you don't want it peaked. This is the reason air compressors and air conditioning compressors have unloaders or pressure switches that keep them from starting until pressure has equalized in the system, to prevent startup under full load. Also the same reason there is a measured amount of slack in railroad car couplers: The engine can't overcome static inertia of the full string of loaded cars at once, but can start them rolling one inch at a time, one car at a time due to the slack. This is why you want the bullet to be already moving when it encounters the resistance of squeezing through the throat and engraving unless using a powder that's slower-burning and going to build pressure more slowly anyway.

Slower powders like 4198 will build pressure more slowly even with the added resistance of starting the bullet from standstill plus overcoming engraving resistance, and you can use that to your advantage to get a better powder burn, but for now give the bullet some wiggle room and you can play with seating depth later.

Like Fiver said, keep backing the sizing die out until it doesn't size your 'necks' down any more than enough to hold the bullet. Your expander spud will not touch the sides, just use it to apply a slight bell to get the bullet started.

Listen to Fiver. He is the master of brevity, I am obviously not, I just put my two cents in with hopefully enough detail that if you don't understand what he means you can reference the long version and hopefully extract the meaning you're looking for.

 

[Ian]

21 grains of IMR 4198 will give you around 15K PSI, not CUP. That would be a good starting point. I reference pressure in PSI to relate it to BHN, which has limited usefulness but it's nice to know when your alloy will start to flex and start to deform permanently.

 

[Chris C]

Ian, your explanation was perfect. I got it..........from start to finish. I like analogies. This one made all the sense in the world to me. Thanks. (I use analogies all the time with my wife and she just rolls her eyes and never gets it!)

Okay, so here's the plan:

*Use "as cast" bullets
*Adjust sizing die to produce .378" ID on brass
*Use just the tip of the brass expander to make flair
*Seat bullets at 2.520" COL
*Crimp with Lee Factory Crimp Die to .394" (just enough to remove flair)
*Use IMR4198 starting with 21 gr.
*Go up .5gr for each of 5 targets, 10 shots each

Does that sound like a good place to start? I'll start lubing bullets tomorrow. I'm pumped! This is more help than I've had in the 5 years I've been shooting and loading.

 

[Josh]

These guys have helped me with all kinds of off the wall projects, this one isn't off the wall but their input is even more valuable because they can see a point to the testing. (sometimes I can be a bit excntric in my ideas, ask about a 260 gr bullet in a 30-06) If you follow their advice, I will guarantee you will get where you need to be.

If in this quest you need a new bullet design that works for your rifles throat better, I will be happy to get one made up for you. It takes a few drafts with the input from these guys, but we have produced more than one great design here.

 

[Ian]

Sounds good to me, Chris.

Remember what Rick said about taking notes. You will probably get some 2 or 3" groups in this process, but that data is as valuable, if not more so, than ragged hole groups when you're doing a workup. Big groups aren't a failure, they're a learning tool, so don't get discouraged if you don't achieve your accuracy goal tomorrow. You need to know what each part of the loading process actually does, you know, the EFFECT. To really understand the rifle and how to get consistent loads, you need to understand the effects of different seating depths, neck tension, loaded neck clearance, different alloy makeups, powders, even primers, just to name a few of the things you can control and manipulate to get the load dialed in. And since one variable affects another, it's often difficult to find meaning from the data, but hopefully we can help sort it out for you.

Take good notes about everything you did to the brass, the bullet, and the usual particulars about powder, primer, OAL, etc.

Only change one thing at a time.

Don't draw hasty or false conclusions from the results you get. For example, if you have good luck seating to touch the throat with one powder, and have concluded that it always shoots better that way, you will be a bit frustrated getting similar results with a different powder, or tougher alloy, so "always" is really pretty much a "never", you just have to keep trying things until your rifle tells you it likes what you did and don't extrapolate too much meaning from any one thing you discover.

 

[Chris C]

If in this quest you need a new bullet design that works for your rifles throat better, I will be happy to get one made up for you. It takes a few drafts with the input from these guys, but we have produced more than one great design here.

I designed the bullet I'm casting....................but, admittedly, I know absolutely nothing about bullet design. I just took a design that had been working for a lot of the guys on a forum I frequent and basically had it made longer because I'd been told with my 1:14 twist I needed a bullet over an inch long. So what does a service like yours cost?

Remember what Rick said about taking notes. You will probably get some 2 or 3" groups in this process, but that data is as valuable, if not more so, than ragged hole groups when you're doing a workup. Big groups aren't a failure, they're a learning tool, so don't get discouraged if you don't achieve your accuracy goal tomorrow. You need to know what each part of the loading process actually does, you know, the EFFECT. To really understand the rifle and how to get consistent loads, you need to understand the effects of different seating depths, neck tension, loaded neck clearance, different alloy makeups, powders, even primers, just to name a few of the things you can control and manipulate to get the load dialed in. And since one variable affects another, it's often difficult to find meaning from the data, but hopefully we can help sort it out for you.

Take good notes about everything you did to the brass, the bullet, and the usual particulars about powder, primer, OAL, etc.

Only change one thing at a time.

Don't draw hasty or false conclusions from the results you get. For example, if you have good luck seating to touch the throat with one powder, and have concluded that it always shoots better that way, you will be a bit frustrated getting similar results with a different powder, or tougher alloy, so "always" is really pretty much a "never", you just have to keep trying things until your rifle tells you it likes what you did and don't extrapolate too much meaning from any one thing you discover.

Believe me, I'm trying to remember everything you've told me. I'll do the best I can to get everything right. I'm going to go lube bullets tonight and will start working up 50 test rounds tomorrow afternoon after I get back from the gym. Will try and shoot them on Wednesday. (gotta vote on Tuesday)

Thanks again for all your help. Needless to say, I'll follow up with a range report.

 

[Ian]

Good luck!

 

[Josh]

I designed the bullet I'm casting....................but, admittedly, I know absolutely nothing about bullet design. I just took a design that had been working for a lot of the guys on a forum I frequent and basically had it made longer because I'd been told with my 1:14 twist I needed a bullet over an inch long. So what does a service like yours cost?



Believe me, I'm trying to remember everything you've told me. I'll do the best I can to get everything right. I'm going to go lube bullets tonight and will start working up 50 test rounds tomorrow afternoon after I get back from the gym. Will try and shoot them on Wednesday. (gotta vote on Tuesday)

Thanks again for all your help. Needless to say, I'll follow up with a range report.

I don't charge anything but the learning experience, every time we get to brainstorming (like this thread) I learn more than money can pay. Admittedly I haven't brainstormed in this thread but I have read every post. Some things I knew, some needed refreshing, some I learned. I was in no way saying your bullet wouldn't work, only if you think another design may get you further down the rabbit hole I am happy to help.

This project has my interest, I have not played with a rifle like yours or your caliber so this is all a learning experience for me.

 

[Chris C]

Good luck!

Thanks.........I'll need it. Turns out I had to use a neck expander that gave me a .377" ID because I had no fired and un-sized brass. But I think it will be okay for this test.

I don't charge anything but the learning experience, every time we get to brainstorming (like this thread) I learn more than money can pay. Admittedly I haven't brainstormed in this thread but I have read every post. Some things I knew, some needed refreshing, some I learned. I was in no way saying your bullet wouldn't work, only if you think another design may get you further down the rabbit hole I am happy to help.

This project has my interest, I have not played with a rifle like yours or your caliber so this is all a learning experience for me.

Well, welcome aboard my journey train. Might holler at you down the road if this bullet turns out to not work. I've also got a good chamber cast that I can send to Veral Smith at LBT. I've heard he will send a bullet based on your cast that's more accurate than anything you'll find on the market. Of course, that's Veral sayin' it..........and while everyone I know who has one or more of his molds say they cast better than any other mold they own, no one yet is willing to claim it's the most accurate bullet they've got.

 

[freebullet]

If you had THE bullet for your rifle you would notice it working really well over a spectrum of alloys, loads, powders ect.

Can't wait to hear about your next set of results.

 

[Chris C]

I know............but the search for THE bullet is like searching for the Holy Grail. Maybe someday I'll find it.

 

[fiver]

a LOT of people have learned from Veral.
I don't think either he or Walt Melander get the credit they deserve for their contributions.
I probably should read Veral's book someday.

 

[Brad]

His book is an interesting read. Things like not weigh sorting until after sorting by diameter as cast. A .001 fatter bullet with an internal void may weigh same as the smaller bullets with no void. Kinda changed my view on sorting by weight.

We got where we are today because of work done by those men in the past. We owe them a big thank you.

 

[fiver]

Chris you don't search for the bullet.
you have what you need right there in that picture to make the bullet for your rifle.
the rest is just details.

 

[Chris C]

a LOT of people have learned from Veral.
I don't think either he or Walt Melander get the credit they deserve for their contributions.
I probably should read Veral's book someday.

I've got it. Bought it after a long telephone discussion with him. Very interesting guy, to say the least. You should read it, it's worth both the time and money. In fact, I think I'll read it again just as a refresher.

His book is an interesting read. Things like not weigh sorting until after sorting by diameter as cast. A .001 fatter bullet with an internal void may weigh same as the smaller bullets with no void. Kinda changed my view on sorting by weight.

We got where we are today because of work done by those men in the past. We owe them a big thank you.

You get a double "Yup" from me on that one.

Chris you don't search for the bullet.
you have what you need right there in that picture to make the bullet for your rifle.
the rest is just details.

Hmmmmm. Interesting statement. I'll withhold agreeing with you until I see some results.