270 COAL with Lyman 280468s

[dsh1106]

High guys
I've got a question that I think I know the answer to, but I'm looking for concurrence.

I'm working on a plinking load for my 270 using the Lyman 280468"s" boolit (109 grain), the only data I have for the Lyman 280468 is for the "LONG" (119-122 grain). If the COAL using the Lyman 280468"l" is 3.069, would the COAL using Lyman 280468"s" be the difference of the two boolits?

The Lyman 280468"s" is approx .100" shorter than the Lyman 280468"l". Using this logic the bullet base of the Lyman 280468"s" would be at the same depth as the Lyman 280468"l".

Does my logic make sense?

Any help on this would be awesome.
Thanks
Scott

[GabbyM]

The difference in bullet weights I believe is all in the body. Nose is the same so COL should be the same. Mine is one of the 122 grain bullets. I load it to the rifling minus .015" to ensure easy bolt closing. case mouth ends up in the second lube grove. 14.0 grains of Unique under this bullet works great. No fillers or anything to mess with and velocity is as fast as I can run bullets from the 270. Lyman's old book shows this load at 1,875 fps and the accuracy load. It's not very scary but an up side is you can shoot rapid fire without heating the barrel up to fast. I don't use or recommend a crimp with a low recoiling load like these. I use a Lyman M die to expand case necks. RCBS makes a good expander also. There new style is just like an M die with better steel.

[dsh1106]

Thanks for the info, GM

I did some comparing of the two boolits at work on the comparator, you are correct in say the difference is the body length. I put a sample together at 3.069" as shown in the LYMAN cast bullet handbook 3rd edition for the 280468"l", but with the 280468"s" there wasn't enough bearing surface to keep the boolit in place straight.

I made another sample at 2.969", at this depth I have the same case engagement on the SHORT boolit that I have with "LONG" boolit set to LYMAN's data. There is one full drive band showing along with the top lube groove.

I'm attaching a picture of the two above mention samples
left is the 280468"l" @ 3.069"
right is the 280468"s" @ 2.969"


Thanks
Scott

EDIT -
Using this boolit style the COAL when touching the lands on my rifle is 3.095"

[GabbyM]

Have you tried to chamber one up? I know the one you picture on the left would not chamber in my Weatherby Vangaurd.
your overall length is determined by the length of your chamber throat. I chose to load mine just short of engraving rifling in the bullet nose ogive. I tried some where they engraved a 1/8" grove but they didn't shoot any better and were just harder to close the bolt on. If I get a bullet stuck when testing length. I've a 1/4" x 3 foot brass rod I bought at hardware store for a few dollars that taps them right out. My loads end up with the 122 grain boolits gas check at the bottom of the case neck. I think they are deeper than the one you picture on right.

[dsh1106]

Both of the samples shown will chamber without any issues. I have made a "MAX" COAL sample for every bullet & boolit that I reload for my rifles.


The above mentioned boolit 280468 "s" or "l" touching the lands on my rifle is 3.095"

The left sample is the 280468"l" (appox 119gr) COAL @ 3.069", .026" short of the rifling
The right sample is the 280468"s" (approx. 109gr) COAL @ 2.969", .126" short of the rifling

Thanks
Scott

[gwpercle]

I like to seat the boolit so that the gas check is just above the shoulder/neck junction, the idea being to have as much boolit held in the neck without the base/gas check dropping down in the shoulder area. If they feed into and out of the chamber easily, start there. You can play with seating depth after that. A lot has to do with each rifles individual chamber. OAL is not an absolute dimension that must be adhered to, the rifle, chamber and throat will determine that length.
Gary

[GabbyM]

Well Scott you have a very long throat on that rifle.
I'd do as suggested by gwpercle. Just load some up and shoot for effect. Good chance they'll shoot just fine.

[dsh1106]

Well I finally had found some free time to pour some of the 280468's.

It took awhile to get things to come out right, but I finally got some of both the "L" and "S" poured.

I took my time and ended up with 20 of the 280468L and 23 of the 280468S

AVG weight of the 280468L with a gas check was 117.3 grains,
high of 117.9 grains
low of 116.6 grains

AVG weight of the 280468s with a gas check was 108.05 grains,
high of 107.9 grains
low of 108 grains