BIB bullet quandry

Travelor

New member
I have been shooting Bart's bullets in my 30BR that was chambered by Dusty Stevens with a Robinette reamer and everything has gone well. But while waiting for a response to a question posed to Bart thru Dusty I purchased some BIB 112 grain bullets after reading the NBRSA match equipment lists.

I was working up the seating depth when I have ran into a problem. The BIB bullets when seated in the cases (that work just fine with Bart's bullets) will not chamber due to the case necks being expanded about .005" larger than with the Bart's bullets.

I know, my chamber and neck walls are tight, but has anyone else run into this before?
 
I am hoping

I have been shooting Bart's bullets in my 30BR that was chambered by Dusty Stevens with a Robinette reamer and everything has gone well. But while waiting for a response to a question posed to Bart thru Dusty I purchased some BIB 112 grain bullets after reading the NBRSA match equipment lists.

I was working up the seating depth when I have ran into a problem. The BIB bullets when seated in the cases (that work just fine with Bart's bullets) will not chamber due to the case necks being expanded about .005" larger than with the Bart's bullets.

I know, my chamber and neck walls are tight, but has anyone else run into this before?

you forgot a zero. Don't you mean .0005 rather than .005?

That said. Randy's bullets tend to be "fat". I have shot his 118's and 114's for the last 15+ years and for the most part they have measured .3088 at the pressure ring. If the size difference is what you are seeing, then #1 you are running a tighter neck than most 30BR shooters and #2 you should turn your brass for a .0015 to .002 loaded clearance. That will solve your problem.

David
 
I think you need another 0 in that measurement, BIB 118's have a pressure ring measurement of .3086 and I would assume the 112's are similar, If Barts are .005 smaller they would measure .3036 and I'm quite sure they won't. If .0006 pressure ring won't chamber you are running way to tight on your neck clearance and asking for trouble. Please get this figured out before you shoot this gun anymore so you don't get hurt.
 
I have been shooting Bart's bullets in my 30BR that was chambered by Dusty Stevens with a Robinette reamer and everything has gone well. But while waiting for a response to a question posed to Bart thru Dusty I purchased some BIB 112 grain bullets after reading the NBRSA match equipment lists.

I was working up the seating depth when I have ran into a problem. The BIB bullets when seated in the cases (that work just fine with Bart's bullets) will not chamber due to the case necks being expanded about .005" larger than with the Bart's bullets.

I know, my chamber and neck walls are tight, but has anyone else run into this before?

I bought 5K of Bart's 112's and the pressure ring measures .3081. I have 4K Bib's 112's, 3 different lots and they all measure .3089 at the pressure ring. Big difference. I have usually 2 different neck thicknesses for the 8 different manufactures bullets that I use.
 
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I have been shooting Bart's bullets in my 30BR that was chambered by Dusty Stevens with a Robinette reamer and everything has gone well. But while waiting for a response to a question posed to Bart thru Dusty I purchased some BIB 112 grain bullets after reading the NBRSA match equipment lists.

I was working up the seating depth when I have ran into a problem. The BIB bullets when seated in the cases (that work just fine with Bart's bullets) will not chamber due to the case necks being expanded about .005" larger than with the Bart's bullets.

I know, my chamber and neck walls are tight, but has anyone else run into this before?

I guess we all view the world through a different lens :)

I shoot a lot of types of bullets and never expect them to "interchange"

I make cases (and chambers, and in fact entire rifles) around specific bullets.
 
I have been shooting Bart's bullets in my 30BR that was chambered by Dusty Stevens with a Robinette reamer and everything has gone well. But while waiting for a response to a question posed to Bart thru Dusty I purchased some BIB 112 grain bullets after reading the NBRSA match equipment lists.

I was working up the seating depth when I have ran into a problem. The BIB bullets when seated in the cases (that work just fine with Bart's bullets) will not chamber due to the case necks being expanded about .005" larger than with the Bart's bullets.

I know, my chamber and neck walls are tight, but has anyone else run into this before?

As others have stated, your figure surely lacks a ZERO! :eek: The 112 Gr. bullets you purchased should measure 0.3087" across the heel (pressure-ring), and .3083" on the shank. Some older LOTs of J4 jackets would make a P-R as large as .3088", along with the [usual] .3083" shank diameter. The Hines/Allied Precision Tool jackets (sold by Bart's and StaMoly) have been pretty consistent, at .3083" shank, with .3085- .0387" P-R - about average, but for the Niemi dies, tending toward the small end of the P-R range.

When measuring 1/10ths of one thousandth of an inch, one should verify the micrometer via a standard - even then, the instrument may display +/- 0.0001", depending upon user, and/or, many other factors. I verify micrometer calibration to a standard daily - often several times.;)

Seven ogive BIB bullets , depending upon jacket LOT, have run from 0.3085" (rare with J4) to 0.3088" (unusual), with .3086-7" being the overwhelming "norm". I have always turned [thirty caliber] case necks to 0.0098", which usually results in loaded-round neck-diameter of .3282 -.3283", or, .0017" to .0018" of total clearance for a .330" chamber neck diameter. With my .0098" neck-wall thickness, a true .3080" heel/pressure-ring would result in a loaded-round neck diameter of .3278", or, .0022" of total clearance. The BIB thirty caliber dies were made to make the shank diameter .3083" - the pressure-ring is a variable, which is, normally, of little consequence.

It would appear that you have been shooting the BARTs with minimal neck-clearance - probably 0.0005" , or, less.
I'd predict much better Agging capability if you turn necks to 0.0010" wall thickness, or slightly less. Assuring that total clearance is .0015", or greater is usually desirable. While "fitted necks" can work, not many individuals even attempt it any more. Good shootin'! RG
 
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I agree with Randy. You are shooting, (based on my experience), too tight of a loaded round, even with the Barts.

I turn my necks to .0098 thick, (.330 neck).They work with both the Barts and the BIB with a .325 bushing.

By the way, the Barts 112's I have measure .3083 on the gas ring.
 
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