I'm just getting started reloading for my .270 and I ran into a little problem. I bought a Stoney Point OAL gauge and comparator set and a box of Remington Core-Lokt 130 grain bullets. I followed the directions and set it up exactly as described but when I removed the case and bullet I noticed the bullet is barely seated in the case. I measured it and compared it to a factory round with the same bullet weight and the gauged round is .168" longer. The cannelure grooves are also way past the case neck. Is it typical to see this much of a difference as compared to factory loaded ammo, or is the throat just plain shot out of this gun? I can't beleive it would be worn that much. Its a Remington 700 ADL and the rifling looks just as good as new to me. Here's a picture of what the gauged round looks like against a bullet, it seems to be barely seated in the case:

Rowdy, you just started learning a bit bout cartridge OAL; It ain't written in stone!

When ammo makers submit designs to gun makers for a cartridge they usually do so with the longest/heaviest round nose bullet expected to be used in that cartridge. Max OAL is - usually - determined for safely seating that bullet to the base of the neck. Gun makers match it to their proper action/magazine length and throat the chambers for that longest bullet.
They have to do it that way, if they throated for lighter bullets all heavier ones would be jammed into the rifling and pressures would jump a lot.

Any bullet lighter than max can can be set further out, to a point. Your bullet is pointed and a bit less max for a .270 so you are seated out a bit, but not too far, IMHO.

Bullet makers tend to put their cannalure where it will match common factory loads but that isn't a hard rule, they vary a bit.

Reloaders generally want to seat bullets at least one full caliber deep but that isn't fixed either. Sometimes bullets are seated in or out a bit.

By my calibrated eyeball, and in my opinion, it looks like your loaded round has the bullet seated about right but I'd suggest you go maybe .020" deeper and test for accuracy. After you find the best power charge you may want to move the bullets in and out in a couple of .010" increments to see if it improves accuracy.

For now, you only want to make sure the ammo feeds from your magazine AND the bullets aren't jammed hard into the rifling. Looks like you are off to a good start!

Good luck!

Your OK. Is that a 130 gr? A 150 will be deeper in the neck.

All my canalur grove bullets are with the groove out.

Factory rounds are loaded pretty short compared to how I reload to get close to the lands

Your oal length to the lands will vary with different rifles

just seat it about .010 .020 ++ from the lands

Measure your mag box and see how long you can go , it should be fine with the 270

Yep, I have the same thing in my 270 in a 700 action. The chamber just have a long throat.

Whew...thanks guys!
This is a 130 grain bullet just as I pulled it from the chamber after seating it against the rifling. I planned on seating it about .015" off the lands to start with, but after seeing how far out the bullet sits right now I was concerned it still wouldn't be seated deeply enough. I have the cases all charged right now, but I think I'll load up a dummy round first and make sure it feeds and chambers before I load up a whole batch. I have the cases loaded with 52 grains of Hodgdon H4831 so I think I should be within safe limits for pressure.
Just out of curiousity, about how many rounds can be fired before I start to notice throat erosion? I've had this rifle for about 11 years but I've fired less than 50 rounds through it since I've owned it. I bought it used but it was only about a year old at the time so I doubt the previous owner shot it much.

Must of my rifles are over 50 years old some like new condition and a see no throat erosion in any. The big case cartriges like 264 mag ,7mm stw , might erode the lands

Talk about long throat My husky 9.3x57 has the longest ive seen. A 286gr 9.3(.366 cal) bullet only puts the bullet about .010-.020 into the neck. Barely hanging there. I just load it about .360 into the neck. So it has a big ol' jump to the lands

You have 2 options. And 2 important things to consider.

1. accuracy with respect to ogive/lands seating depth.

2. accuracy with respect to adequate neck tension.

From what I can see, it is my opinion that the bullet needs to be seated a bit deeper to begin with for the first few rounds. You want at least 2/3 of the case neck to contact the bullet, and it doesn't appear to be there. Too little neck contact can be a problem. I'd find a load with good neck tension first, then try to seat the bullet out more so the ogive is closer to the lands and see what happens.

Well it looks like you are hosed. Those Sinclair depth gages work just great on match barrels with short throats. The match shooters adjust their seating depths as the barrel wears. And those match barrels are typically cut with custom reamers. Your rifle is a factory rifle and the reamer is probably cut to ward off evil lawyers and law suits.
Seat the bullet OAL just a little less than magazine length and go out and shoot the thing. This is not a target rifle why try to reload like it is?


Unless you practice every other day, your off the bench groups will be about three or four times larger than your bench group, so stop messing with target and bench rest reloading technics and just practice. That will improve your group sizes one heck of a lot more than benchrest reloading techniques.

quote:

Originally posted by rowdyredneck:
I have the cases loaded with 52 grains of Hodgdon H4831 so I think I should be within safe limits for pressure. Just out of curiousity, about how many rounds can be fired before I start to notice throat erosion?

In my 'old' Sendero .270, with H 4831sc, 130 grain Sierra's I noticed a throatwear of .004" every 260 rounds. With my Stoney Point gauge and comparator, it was very easy to measure. I am now using the same Sendero, but mounted with a custom stainless barrel and erosion seems to be less.
Your charge is (IMHO) on the very low side, velocity about 2700 fps. A lower than minimum charge endangers the 'safe limits' as well, cause the combustion could be more irregular. You could go up for the 130 grainers to 57 to 60 grains H4831sc, you will probably not exceed the safe limits, your velocity could go up to 3100 fps and your accuracy is likely to improve.

I do not totally agree with Slamfire:
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Unless you practice every other day, your off the bench groups will be about three or four times larger than your bench group, so stop messing with target and bench rest reloading technics and just practice. That will improve your group sizes one heck of a lot more than benchrest reloading techniques.
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He has absolutely right with his statement that a field position garantees a group even two to six times larger than at the bench, depending on your firing position (offhand, sitting, solid rest). Practice can improve this, but you will never get the same results as at the bench (buck fever!). So when you start at the bench with an accuracy of about 1 MOA, your field groups in your favorite position could be four times larger, 4 MOA. So if you are satisfied with 2,5 MOA at the bench, the field position will be about 10 MOA and 4 to 10 MOA makes a huge difference in hitting correctly. So in my opinion it is always wise to develop your load for the best possible results at the bench and do a lot of practice training to improve your skill. And there Slamfire is right again!

A happy New Year to you all!
Jan.

quote:

Originally posted by rowdyredneck:
Is it typical to see this much of a difference as compared to factory loaded ammo, or is the throat just plain shot out of this gun? I can't beleive it would be worn that much.

Yes that is a typical chamber, not an aberration. Both of my 270s (as are all my other rifles)are like that. When I seat TSX in one rifle I can see two of the "rings" and in the other one. Both rifles will place three bullets in the same hole- I can't........usually stop at two...

.010 off the lands is not the "holy grail" and not necessary. In fact with some bullets you get high pressure if your less than .050 off the lands. I vaporized a primer with a max load of a hotter powder .010 off the lands with TSX.

Neck tension is a function of pressure over the bearing surface. Having less bullet in the neck is irrelevent, of course up to a certain point.

(Remember what all those idiots used to say when the .300 Win was introduced as compared to the .308 Norma mag....."it can't shoot that accurate, the neck is too short"........WRONG)

You can use less "pinch" (diameter effect) over a greater bearing surface (bullet seated deeper) or greater "pinch" over a lesser bearing surface to get the exact same neck tension. I don't remeber off hand, but I'd like to say I use .001in neck tension (bushing) in my .270s and .007in my 340 WBY (custom short throat in that one).

Don't sweat it, you'll be fine. Find the greatest COAL that will fit in the magazine, and use that as your starting point in conjunction with your "length to lands" measurement.

I loaded up a few dummy rounds this morning and seated them .020" off the lands based on the measurment I made with the OAL gauge. They fit my magazine and will chamber and eject just fine without pinching the bullet so I'm using that as a starting point.
I also dumped the charged cases and refilled them with 56 grains of H4831. I'm not comfortable pushing the limits and from the load info I have this should be about a mid range charge for this powder. Next time I'll use short cut, this stuff doesn't meter the best from my measure. I weighed a dozen charges and had as much as 56.3 in a few but nothing under 56. I have to send my scope in for repair so it may be a few weeks before I can test these rounds. I just wanted to load them up now while I have the weekend off work and have some time to do it.