I'm looking to build a 458 American on a M70 Classic WSSM Action and I think the longest I'll be able to go with COAL is 2.46". This is going to be an Eastern Woods Thumper so I am not super concerned with loading exceptionally heavy bullets. I would build a clone of this on a WSM action instead if I wanted to really juice this cartridge and load out super far. I am looking at modifying the mag box and bolt stop and may be able to snag another .2" but before I do that, I am looking at what length these longer bullets are being loaded to. The drawing on Wikipedia shows 2.44” but that could be loading bullets exceptionally deep or the max length with the shortest, lightest bullet on the market.
The bullet length for the 300 gr Barnes TTSX is 1.235” while the bullet length for the 300 gr Barnes Original FN is 0.792” and for the 300 gr Barnes Original Semi-Spitzer is 0.941” so there is quite a length range within the same weight and there are even some 400 gr options that are shorter than the TTSX. I know bullet length also doesn’t tell the whole story due to differences in Ogive and Tip Shape which would affect how much sticks out above the top of the brass so long story short, what bullet are you using, how long do you load it out to, and how short could you go before getting into the ogive?
The bullet length for the 300 gr Barnes TTSX is 1.235” while the bullet length for the 300 gr Barnes Original FN is 0.792” and for the 300 gr Barnes Original Semi-Spitzer is 0.941” so there is quite a length range within the same weight and there are even some 400 gr options that are shorter than the TTSX. I know bullet length also doesn’t tell the whole story due to differences in Ogive and Tip Shape which would affect how much sticks out above the top of the brass so long story short, what bullet are you using, how long do you load it out to, and how short could you go before getting into the ogive?
