Seating Depth 30 cal 180gr. Barnes TTSX

[Williamb]

I just decided to load-up some 300WSMs with the 180 grain Barnes tipped TTSX bullet. Using the load data in their latest reloading book and using the C.O.A.L for the MRX bullet at 2.825"(appears to be similar design with plastic tip) the first driving band of the bullet (toward the tip) is fully exposed. Only when you seat the bullet to an O.A.L of 2.79" are all the bands fully covered by the case. The case was trimmed to 2.09" which is recommended.

Wondering what your experience has been. Have you seated the bullets with the driving band fully exposed or have you seated deeper to fully cover it up. Went to the Barnes website looking for info but did not find any. Any info here would be appreciated.

Thanks -

 

[yorke-1]

I haven't worked with the 180 TTSX, but I did use the 168 TTSX. I seated them .035" off the lands without worring about whether I landed on one of the bands or not.

I will say the the 180 MRX and the 180 TTSX are verry different. The 180 MRX is shorter in length than the 168 TTSX, so I imagine it is considerably shorter than a 180 TTSX. I don't think that the loading data is interchangable.

 

[yorke-1]

Sorry, I just checked the Barnes sight and the data for the TTSX and the MRX is the same, so ignore what I said about that.

 

[Williamb]

I haven't worked with the 180 TTSX, but I did use the 168 TTSX. I seated them .035" off the lands without worring about whether I landed on one of the bands or not.

.

I would agree with you. I worked up some dummy loads .050" off the lands as a starting point. I am using a Kimber 8400. That put the nominal OAL at 2.88 and has one band exposed. The Barne's manual says COAL as 2.825 but their website also recommends loading off the lands between .030 to .070". That recommendation will clearly exceed the COAL for most production rifles and will definitely expose the band(s). I would have thought that either on their website or loading manual some mention of seating depth and bands showing would have been mentioned.

Thanks -

 

[Williamb]

I talked to Barne's this morning. They stated that the bands showing or not showing has no relevancy to accuracy. All other reloading truisms about seating depth still hold.