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Re: Throat length question for .308 and 7mm-08
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Hey Jim, The actual answer is not as simple as it initially appears. You also have to take into account the actual Bullet "Nose Profile".

For example, if you would get a box of Sierra or Speer "Round Nose(RN)" Bullets, you might actually have to Seat them deep(say 2.55" or so) to keep them "Off the Lands" in a 2.8" magazine. Not necessarily true with a Hornady RN, because a lot of them are 2-diameter designs.

You might even be able to reach the Lands with a regular old 150gr or 165gr Speer Hot-Cor because the Nose Profile is not as sleek as most of the other Bullets.

However, there is some good news for you. Being able to "Kiss-the-Lands" may or may not be accurate in your rifle anyhow. If your magazine is 2.8" (as a lot of mine are), just Seat the bullet at 2.775" or so and Develop your Loads from below. Once you know where to STOP adding Powder for your rifle, due to the Pressure Indicators, back off a bit and adjust the accuracy by "Varying the Seating Depth". In your situation, that would mean Seating "Deeper" in increments of your choice (0.005", 0,010", etc.)

One of my rifles has the Bullet 0.268" Off-the-Lands and is extremely accurate with that Bullet. You just don't know until you try.
 
Posts: 9920 | Location: Carolinas, USA | Registered: 22 April 2001Reply With Quote
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When you seat bullets to touch or nearly touch the lands in your factory .308 and 7mm-08 rifles, what is the loaded round's over all length? Or vice versa, when you seat to fit a 2.8� magazine, how far is your bullet from the lands?

On my Model 700 .308, when I seated typical Hornady 150 Spire Points to fit the magazine I was about .100� from the lands � yes, that�s one tenth of an inch.

I thought maybe it was just Remington .308�s but now a smith tells me that this is a problem in a lot of .308�s and 7mm-08�s because the standard chamber reamers produce throats too long.

How are you guys with the Winchesters? Can�t own a right handed Winchester short action but don�t they have a 3� magazine box? Can you touch the lands and still fit the magazine? I know Mel Forbes makes his Ultra Lights with 3� boxes just to overcome this problem.
 
Posts: 1027 | Registered: 24 November 2000Reply With Quote
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I have a Win Featherweight in 7-08. It doesn't seem to have a long throat. 120 Barnes XBT's are on the lands at about 2.87". Remington 140 PSPCL's are on the lands at about 2.86". The magazine will accept and function with a COL of 2.84". I had measured the COL with Sierra bullets on the lands, but I don't see it in my notes. IIRC they came out shorter than the Remington and Barnes bullets. Not bad in my estimation.
 
Posts: 279 | Registered: 31 May 2004Reply With Quote
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