Ruger 77 freebore longer than book COAL

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OlympicViking

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Just used the Hornady tool for determining bullet seating depth. With a 120 gr Barnes TTSX I repeatedly got 2.910" in my Ruger 77 Hawkeye in 7mm-08. SAAMI COAL is 2.800". I made a dummy round 2.910" long that chambers without resistance but is too long for the magazine.

My RCBS precision mic has a 2.850" dummy round as being exactly .050" off the lands, but it should be noted that the freebore measurement with the mic is based on their freebore tool rather than the actual bullet I will use. I figure the two are close but not exact.

I planned to seat the Barnes bullets about .060" off the lands, but that still puts me above book max COAL. At 2.850" the dummy round chambers & fits in the mag. What would you guys do?
 
I'd go with 2.850 if that is the longest OAL that will work with the gun. Max book COAL is helpful as a reference, but going longer to fit a specific gun isn't going to hurt anything. The rounds might be too long to work in other guns but I'm guessing that is not a concern at this point.
 
Well, welcome to the real world. It differs a bit from he the Internet. In fact, it differs A LOT.

MANY rifles have chambers longer than the magazine will handle. That's life.

Load as short as you want, or as long as the magazine will handle. Your choice.
Many rifles are perfectly accurate without loading within 0.020" of the lands.
Some are not accurate with a long jump, you'll have to let the gun tell you it's own story.
 
Barnes didn't ream the throat in that Ruger, so they're probably not a good resource for determining appropriate seating depth in this case.

The mono metal Barnes bullets have universally preferred longer jumps for me. On the order of 50 thou and larger. I had all but given up on them a few years ago when another user at huntingnet.com helped me out.

Load to mag length and live with a lot of jump, or live with feeding single shot.

What you experienced with the RCBS precision mic tool is the exact reason it is not an effective tool - it does a lot of things well, but that substitution for the bullet cripples it's effectiveness for that purpose. Different ogives = dofferent contact points on the leade, so a guy can't use that length any more than he could use the wrong bullet to get the right length.
 
Like the guys have posted, stop worrying about chasing the lands, load it to the book OAL, and work up a load. Odds are if it is going to shoot in your rifle, it will do so there.

I'd be cautious about loading solid metal bullets like these close to or at the lands in any rifle. I have no data to base that on, but it isn't in my comfort zone.
 
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Roy comes to mind--Weatherby that is.
Or Maybe just a touch of Ruger's excessive machining tolerances?
On other hand, see what magazine will accommodate and proceed from there.
But in any case, always work up that load slowly.
 
Varminterror said:
Barnes didn't ream the throat in that Ruger, so they're probably not a good resource for determining appropriate seating depth in this case.

The mono metal Barnes bullets have universally preferred longer jumps for me. On the order of 50 thou and larger. I had all but given up on them a few years ago when another user at huntingnet.com helped me out.

Load to mag length and live with a lot of jump, or live with feeding single shot.

What you experienced with the RCBS precision mic tool is the exact reason it is not an effective tool - it does a lot of things well, but that substitution for the bullet cripples it's effectiveness for that purpose. Different ogives = dofferent contact points on the leade, so a guy can't use that length any more than he could use the wrong bullet to get the right length.
Click to expand...

Ill have to try giving them more jump next time i play with the monometals.
Ive had universally bad luck with them, but i usually load 20tho off the lands or less....if i can.
As stated some magazines just wont let you do that.
 
Do I seat TSX bullets .030 inch to .070 inch from the lands, starting at .050 inch off the lands, as recommended with other X-style bullets?

Yes. All-copper TSX Bullets typically give better accuracy when seated off the lands and grooves (the rifling in the barrel).

From Barnes FAQ. Believe this applies to TTSX, as well.
 
I'd go with the bullet manufacturer's recommended OAL and see how accurate it is. For my reloading, "chasing the lands" is the last item on a long list of accuracy "improvements"
 
If a guy says he has a known jump, he's "chasing the lands" just as much if the number is 10thou or if it is 70tho... throats erode, if you want to stay at 70, you have to chase just as fast as if you wanted to stay at 10thou. Either you're truly chasing your lands - meaning you change your COAL as your throats erode - or you're picking a fixed COAL and sticking. Whether that means you start with a long jump or a short jump is not the same thing as "chasing the lands." No matter what jump you pick, the lands run away if your COAL stands still. Picking a short initial jump doesn't mean you have to chase when they leave.
 
Varminterror said:
If a guy says he has a known jump, he's "chasing the lands" just as much if the number is 10thou or if it is 70tho... throats erode, if you want to stay at 70, you have to chase just as fast as if you wanted to stay at 10thou. Either you're truly chasing your lands - meaning you change your COAL as your throats erode - or you're picking a fixed COAL and sticking. Whether that means you start with a long jump or a short jump is not the same thing as "chasing the lands." No matter what jump you pick, the lands run away if your COAL stands still. Picking a short initial jump doesn't mean you have to chase when they leave.
Click to expand...
Never heard of that term meaning adjusting for throat erosion. I've always used it, and read about it meaning finding the distance from the bullet to the lands for optimum rifle accuracy. As I stated, it isn't very important to me (yes I've tied it and saw very little if anyimprovement) and my "accurate" gun is a Ruger 308 bolt gun that gives me 7/8" groups when I'm on a roll or a consistent 1" with bullet manufacturer's recommendations...
 
Pretty hard to "chase" something standing still, right? As @Bart B. used to point out on here a lot, if you want a consistent jump as your throat erodes, you have to "chase the lands," but most often, it doesn't pay back in precision.

So many folks incorrectly use "chasing the lands" to mean "using a short jump," it has kinda become normal, but it doesn't make it right. Chasing the lands is a pain. Picking and sticking with a short jump is not any different than picking and sticking with a long jump or picking and sticking with your bullet manufacturer's recommendation.
 
I have found over the years, guns that shoot well with long jumps are easier to work with. Short jumps seam to be a lot more picky on the OAL. There are of course a few exceptions, as with most every thing else we deal with. The lead angle and free bore, rifling depth all play in this game.
 
Well, I don't know any celebrities or gun shop gurus, so my use of terminology is jes from experience...
 
As with most Rugers and Remingtons, a case loaded into the lands will not function through the magazine. Your magazine dictates maximum COL. Load to that length or shorter and work up loads from the bottom of the load charts until you get an accurate load. Then adjust seating depth shorter to fine tune. We have had this problem for years, but you can still make them shoot well.
 
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