308 sizing

[chiefpd7]

Just recently started loading 308. I sized the first production at .309. I was using my sizer from my 30-30 boolits. Is sizing 308 boolits at 309 harmful to the rifle?

[Jim]

I seriously doubt it. It would be good, though, to slug your barrel and know what size the barrel wants.

[popper]

No, it won't hurt anything but possibly accuracy and cleaning. I use .310, works fine. Depends on the rifle(groove size) and alloy used. Slug the bbl, give the CB style, GC, application and you will get much more advice.

[chiefpd7]

have never done that and, it seems, difficult at best. Is there an easy way to do it?

[ukrifleman]

I seriously doubt it. It would be good, though, to slug your barrel and know what size the barrel wants.

+1 on slugging the bore to determine the correct bullet diameter. I use .309 cast bullets in many of my .308 rifles with no problems, but my 30-06 M17 Remington needs .311 cast bullets to be accurate.
So slug first, then choose the appropriate bullet diameter.
ukrifleman.

[Jim]

Here is an article on SLUGGING THE BORE (http://www.castpics.net/subsite2/HowTo/Slugging%20the%20Bore.pdf). It's a long read, but very educational.

[chiefpd7]

Just in case it didn't come up (and it appears it didn't for some reason) thanks, guys. Appreciate it. I'll try it after Christmas.

[fishhawk]

Just please don't use a wooden dowel many here found out the hard way......

[williamwaco]

I would recommend you size those bullets .311 for your .30-30 AND for your .308.

[ShooterAZ]

.309 "should" be OK. .310 or even .311 is "probably" better. Only slugging will tell. I slug my bores, but more often than not go .311 in my 30 caliber rifles.

[Lizard333]

Depending on how your barrel was made your barrel can slug anywhere from 307 to 310, depending on how the button was worn or if it was a new or worn broach.

Slugging your barrel is the only way to know for sure.

[JeffinNZ]

I just starting shooting my Husqvarna .30-30 and it will chamber a .312 boolit so that is what it gets. It LOVES them.

Forget slugging the barrel. Take a chamber cast and measure the throat.

[rollmyown]

+ 1 on don't use a wooden dowel for slugging. (yes, I recently found out the hard way)

[mpmarty]

Tough to throw your rifle in the fire to burn out a wooden dowel isn't it.

[Lizard333]

Despite those that tell you that putting anything other than brass or bullets down your barrel will destroy threads, you can use an undersized steel rod of different lengths. Rod A should be 6 inches less than rifle and stock combined. Rod B should be about 8 inches long. Insert rod A through the barrel from the bolt and stand it upright. Insert soft slug smaller diameter than barrel in the end of your barrel. Take rod B and pound the slug to engage the lead in the riffling. Pound out the slug from the rear. Measure the resulting slug with good quality micrometer on the outside of the slug, the largest diameter. Walla!!

Go one to two thousandths over this measurement for your boolits.

Save the wood and cleaning rods for what they were intended for.