Casting Consistency

  • 810 Views
  • Last Post 15 November 2023
Wm Cook posted this 01 October 2023

Regarding long gun & accuracy.  Are you confident enough that you could cast 50 bullets on Monday, come back to the same casting setup on Wednesday cast another 50, size/lube/check them as a group and shoot the same accuracy as if they were all cast at the same time?  Thanks, Bill.

A “Measured Response” is as effective as tongue lashing a stuck door.

Attached Files

Order By: Standard | Newest | Votes
dbarron posted this 01 October 2023

No.  Too many other variables.

Attached Files

  • Liked by
  • Bud Hyett
RicinYakima posted this 01 October 2023

Never tried that, as I almost always cast a full pot, 250 plus in 30 caliber, at a time. That is enough for a weekend national match. 

Attached Files

  • Liked by
  • Glenn R. Latham
  • Bud Hyett
Wm Cook posted this 01 October 2023

Can you give me two variables that would that make the bullets you cast on Monday different than Wednesday.  

The material and methods that were used on Monday are the same as what you used on Wednesday.  The alloy hasn’t changed and the pot is nearly full since you only cast 50 drops on Monday.  

A “Measured Response” is as effective as tongue lashing a stuck door.

Attached Files

Duane Mellenbruch posted this 01 October 2023

Since I cast mostly by "feel" I am pretty sure that my grip force will change even from morning to evening or even during a single session once I start to get tired.  I do not "time" the cooling of the sprue or the cut, so again, this would be a pretty basic variable.  Divots, lumps or flush cut bases are not unknown on my bullets and are part of the inspection after casting. 

To me, casting is a relaxing and pleasurable experience and I just take my time and make bullets.  I am pretty sure that an automated casting machine could be more consistent, but I have no need for that. 

Attached Files

  • Liked by
  • RicinYakima
  • Bud Hyett
Wm Cook posted this 01 October 2023

It would help if I rephrased the question this way.

50 bullets we’re cast on Monday, 50 on Wednesday.  All with the same methods.  They are sized, lubed and checked and kept separate until you shoot a match on Saturday.  Four 5 shot groups are shot in the morning.  Two with what you cast on Monday and two were shot with what you cast on Wednesday.  

The same with the10 shot groups.  One was shot with Monday’s casting, the other shot with Wednesday’s castings.

I did a sloppy job of framing this.  What I’m driving at is whether the bullet to bore fit, thus accuracy, will change from casting session to casting session or for that matter throughout the casting session for the beginning caster chasing cast accuracy .

Will the  250 pcs Ric cast on October 1st be as accurate as another 250 he will cast two weeks from now.  To level the playing field lets standardize things by saying he only uses Linotype from RotoMetal. 

Unless your cadence is mentally fixed I wonder if it can be done without the use of timers/temperature probes.

I left myself a big “out” in that last sentence.  I believe Ric, John, Larry and a number of others on the forum have the cadence locked down.

But for some of us I think the mold temperature could creep up or down and change the bullet to bore fit enough to cause accuracy degradation/fliers.  Thanks for letting me mumble through this.  Bill.

A “Measured Response” is as effective as tongue lashing a stuck door.

Attached Files

  • Liked by
  • Bud Hyett
pat i. posted this 01 October 2023

I didn't have the patience to cast all the bullets I'd need for something like a nationals so used to break it up into 3 or 4 sessions. I didn't see any difference in results.....buts that's just me. Maybe other people's experiences are different.

Attached Files

  • Liked by
  • Glenn R. Latham
  • Bud Hyett
MP1886 posted this 01 October 2023

I didn't have the patience to cast all the bullets I'd need for something like a nationals so used to break it up into 3 or 4 sessions. I didn't see any difference in results.....buts that's just me. Maybe other people's experiences are different.
I agree with Pat, once you KNOW how to cast good bullets you don't have to cast them ALL in one setting. 

Attached Files

OU812 posted this 01 October 2023

Linotype is lots easier to bump or form emmediatly after casting. I have read linotype takes about 24 hours to harden. Some homemade #2 alloys can take longer to fully harden...maybe it's the arsenic percentage?

Attached Files

MP1886 posted this 01 October 2023

I'll tell you another thing about Lino, it will wear the throat out especially if you shoot it at high velocity.

Attached Files

Duane Mellenbruch posted this 01 October 2023

Linotype is lots easier to bump or form emmediatly after casting. I have read linotype takes about 24 hours to harden. Some homemade #2 alloys can take longer to fully harden...maybe it's the arsenic percentage?

It is the higher percentage of antimony. 

 

Attached Files

  • Liked by
  • Bud Hyett
Ken Campbell Iowa posted this 01 October 2023

keep in mind that testing groups from different days of casting ... doesn't mean much until you shoot about 50 or 100 shots per sample ...  even then you are still looking at " probably better or worse " ...

JoeB tells us that small groups are just part of larger groups ...  i am 84 per cent confident that is true ...

ken

 

Attached Files

John Alexander posted this 01 October 2023

I would have no problem with using bullets from two, or three, different days in the same match.  I do it all the time because I seldom get to 200 with my single cavity mold before back pain kicks in. I often need more than 200 for a two day match.

I  don't believe that if all conditions for the two sessions are the same and the sprues change color on the count of 3 or 4 (aka uniform cadence) there will be a difference in accuracy I have tried and can't tell the difference in weight or any difference dimensions with the mike. I don't believe in things I can't see, feel, measure, or weigh.

I think it would take a lot of groups to prove there is a difference. 

For a hundred years it was thought necessary to shoot match bullets i the order they were cast because of imagined difference during the pour.  I think almost everybody has given up on that one.

John

Attached Files

axman posted this 01 October 2023

With a Quality mold, same alloy, same setting on pot. I’d never even consider any difference.

Attached Files

  • Liked by
  • pat i.
axman posted this 01 October 2023

Pat I. Sent you a PM.

Attached Files

MP1886 posted this 01 October 2023

With a Quality mold, same alloy, same setting on pot. I’d never even consider any difference.
The difference is your cadence and mould temperature. 

Attached Files

  • Liked by
  • RicinYakima
axman posted this 01 October 2023

True.

Attached Files

pat i. posted this 01 October 2023

The difference is your cadence and mould temperature. 

But would either one show up on the target? IMO reading the wind and being consistent on the bench will make a heck of a lot more difference in results than a few grains of weight or casting on different days. I'm all for being anal when it comes to casting.......as long as people are being anal about things that matter and not about blindly following the piper with no proof if something does or doesn't make a difference. I have to assume the really good shooters in this BR game don't cast enough bullets in one sitting to last their CBA career. So if casting on different days would make a difference casting in different years should be monumental. BUT they always end up in the top of the ranks.

Attached Files

MP1886 posted this 01 October 2023

The difference is your cadence and mould temperature. 
But would either one show up on the target? IMO teading the wind and being consistent on the bench will make a heck of a lot more difference in results than a few grains of weight or casting on different days. I'm all for being anal when it comes to casting.......as long as people are being anal about things that matter and not about blindly following the piper with no proof if something does or doesn't make a difference. I have to assume the really good shooters in this BR game don't cast enough bullets in one sitting to last their CBA career. So if casting on different days would make a difference casting in different years should be monumental. BUT they always end up in the top of the ranks.
The inconsistancies would have to be great in the bullet weights mainly. You know that if your bullets weigh different there is different amounts of alloy in the bullet. Hard to explain.  If all your bullets fill out the mould cavaty very well, but weigh different then their density is different. That I don't know how much it changes the group at the target. I do know if your bullets weights vary in grains, not tenth of grains, you casting is bad and they aren't going to be the most accurate.

Attached Files

pat i. posted this 01 October 2023

Using a couple grains difference on say a 180 grain bullet was a worst case scenario and like you said you need to look at the way you're casting if that is the case. But has it been proven that even a weight difference that big has an actual effect or is it just assumed? I tested the BC of a couple of different bullets including a 250 grain tapered slick looking 30 caliber pointed bullet out of a Moss mold at 1700 fps and the BC wasn't that high, not near the BCs Lyman claims for their molds. That's why I believe a little wind will open up a group a heck of a lot more than a little difference in bullet weight yet wind flags don't get talked about much but fluctuating bullet weight eats up pages.

Attached Files

Glenn R. Latham posted this 01 October 2023

Bill, the variable I see in you hypothesis might be the hardness of the bullets.  If you're casting wheel weights and air cooling them, they take a good 3 weeks to come up to full hardness.  There will be a little difference between your Monday bullets and your Wednesday bullets come Sunday.  Enough difference to see it on the targets?  If you're "pushing the alloy", maybe.  If you're casting with linotype and shooting mild loads, you're not stressing the alloy and it's likely not an issue.

Glenn

Attached Files

  • Liked by
  • John Alexander
Show More Posts
Close