270 cal bullets B.C., is there a typo??

Wildcat · Mar 29, 2010

Hi, I got a 270WSM lately, and was looking at loading data in the Nolser 6th manual, and noted that the Nosler Bal Tip BC's are rated at .456 for the 140gr and .496 for the 150gr.
Looking at the AccuBond, the 140gr BC is listed at .496

I found the same info on the web site. All other calibers, the Bal Tip & AccuBond BC's match per bullet weight for a same caliber.

Is there an error with the 270 caliber BC listing? Shouldn't the BC for the 140gr AccuBond be .456, the same as the 140gr Bal Tip?

corbin9191 · Mar 29, 2010

According to my exbal program the B.C. is .496

nomosendero · Mar 30, 2010

The 140 AccuBond is a great bullet & to me the all-round choice. Does not appear to be a typo. This rating has held for years, it is a Loooooong bullet.

SJB358 · Mar 30, 2010

That is a good point Wildcat. I have often wondered the same thing. Always forgot to ask though. That 150gr BT is a very sleek, and excellent shooting bullet in my 270WSM. I have crowned it my deer load. Scotty

Richracer1 · Mar 31, 2010

No it's not a typo. Here's the reason. The 140AB has a OAL of 1.310", the 140BT has an OAL of 1.296", and the 150BT has an OAL of 1.350". The longer the bullet for a given caliber, the higher the BC as long as the shapes are similar; AB to BT. The Partition isn't the same shape and is a bit shorter for each weight class thus a lower BC.
Also, the AB is designed with a thicker jacket to get the penetration qualities, so the bullet ends up being longer to achieve the same weight and is a sleeker bullet due to this, albeit minor but it does raise the BC number a little.

I still wish Nosler would also advertise the G7 BC numbers along with the G1 BCs for their bullets, even if it's only on their website. Now if I could only shoot far enough to utilize these good BC rated bullets.

Antelope_Sniper · Mar 31, 2010

The accubonds have a thicker jacket. Since giliding metal is lighter then lead, this lengthens the bullet, and adds to the bc when compared to the BT.

JD338 · Mar 31, 2010

Antelope_Sniper":26bayy68 said:
The accubonds have a thicker jacket. Since giliding metal is lighter then lead, this lengthens the bullet, and adds to the bc when compared to the BT.

Exactly.

JD338

SJB358 · Mar 31, 2010

It still seems a little odd, cause the BT and AccuBond in 130gr's are both virtually the same. I guess it doesn't make a hill of beans difference, although, it is still kinda odd how some are the same and some are different. Scotty