208 Berger LRHT in 0.170" Freebore Chamber

[APGE]

Has anyone tried these in a 0.170" freebore 308 chamber? If so, does the bearing surface sit above or below the neck/shoulder junction on the case?

 

[Ned Ludd]

This is not a direct answer to your question, but may provide some insight. I run the 200.20Xs in a chamber that has 0.180" freebore. The boattail/bearing surface junction is almost exactly halfway out the neck when the bullets are seated at ~0.012" off the lands. A .308 case neck is should be very close to 0.300" long, which means half the neck length is ~0.150". From the chart below, you can see the BTO dimension of the Berger 208 Hybrid is 0.082" longer than the 200.20X BTO. That means the boattail/bearing surface of the 208 Hybrid would be [approximately] slightly less than 1/4 the way out the neck (or about 0.070" above the neck/shoulder junction) when seated at ~.012" off the lands. With a 0.170 fb chamber, the boattail/bearing surface of the 208 Hybrid would be ~0.060" above the neck/shoulder junction, give or take a few thousandths.

I've loaded plenty of heavy bullets seated in about that location in the neck using either Varget or H4895 and they worked just fine. You will likely be running a little higher pressure than you would loading the 208 Hybrids for a rifle with 0.225" to 0.250" freebore, but the boattail/bearing surface junction will still be above the neck/shoulder junction, so it shouldn't be a deal-breaker.

 

[D-4297]

I shot five of them in a .180 FB chamber , .005 off touch , and used a slightly larger than I should have load . No damage was done to the idiot trigger-puller , ( me ) and no damage to the rifle , but that's a serious accident looking for someplace to happen . As has been said in several threads on the subject , a FB of over .220 minimum is needed for these long-assed bullets .

 

[APGE]

I shot five of them in a .180 FB chamber , .005 off touch , and used a slightly larger than I should have load . No damage was done to the idiot trigger-puller , ( me ) and no damage to the rifle , but that's a serious accident looking for someplace to happen . As has been said in several threads on the subject , a FB of over .220 minimum is needed for these long-assed bullets .

Where did the boat tail/bearing surface Junction sit in relation to the case neck? It may be that it's still workable with a more modest charge weight.

 

[Ned Ludd]

Where did the boat tail/bearing surface Junction sit in relation to the case neck? It may be that it's still workable with a more modest charge weight.

Of course it's workable. As I mentioned above, I have a very good load with 215 Hybrids in a rifle that has 0.180" freebore. The 215s have an even longer BTO than the 208. You can't expect to throw the same charge weight under the 208s (or 215s) as you would under the 200.20X bullet having a BTO measurement that is .082" shorter than the 208 Hybrid and not expect to have over-pressure issues. My 215 load runs one full grain less Varget than my 200.20X load in the same rifle. Work the load up properly if you just want to try them out and it will be fine. If you like the way they shoot, you can then have a barrel chambered properly with a much longer freebore specifically optimized for the 208s.

 

[D-4297]

@APGE ; the base of the bullet was approximately almost to the base of the shoulder , maybe 1/32 above the base of the shoulder . Much to deep in the case for my liking , but hey , sometimes ya just gotta . I did , and won't do it again . Never acceptable to push a un-known that far .