Home Forums Reloading Big Game Rifles Headspace variances 270

Hello all,
First post here so i figured id get right into.

Currently am reloading for 270 Win.
My question, after setting LEE fl sizing die on a batch of 1 fired brass, i get varying headspace measurements using the hornady headspace comp. The variance is about +-.002 on the gauge using digital calipers. When i set my first case, i use the gauges to set bump for .002 for a rem 700. After running 30 cases i noticed the variances when checking each case.

Could this be due to different case head sizes? I am using all Winchester 1 fired brass that i have collected over the last year from factory boxes.

If it is useful, my process up to neck sizing is as follows:
clean cases and check all for any issues, lube cases, Fl size after setting on initial case for .002 bump, rotate 90 degrees and put through again (Decapper/expander removed due to concentricity issues), Run through Collet neck die to expand and decap.

I have run similar rounds a few times using other winchester brass and have been producing about 1-1.25 MOA with IMR7828 and RL22 with SGK and SSTs 130. Would really like to improve these groups.

Thank you all
Nick

Virgin brass doesnt always expand to full chamber length on the first firing.
Softness or degree of annealing left around the neck/shoulder area also affect how much your shoulder pushes back.
Some of the BEST brass you have is once fired in your gun.....for that brass use only your collect die...it will chamber excellent.

Btw...was all that brass you collected from one gun and not several....THAT could be the culprit if it came from several.

If you love your 270 get a body die to go with the keep collect.....its fantastic.

When you're carefully measuring "bump" you'll find differing amounts of lube case to case can affect things.

Since you're using a collet neck die, do yourself a favor and get a Redding body die. Right now you're cold working the neck brass more than necessary, and if you eliminate passing anything through an undersize neck to expand it you can also skip lubing the inside of the necks.

All brass collected is fired from my gun. The reason i did fl resize instead of just neck size is because i could not get enough tension on my necks with collet neck sizer, however if i used the mandrel as an expander they came out with good consistent neck tension. I have never annealed cases, but have just done my first batch using the candle method mentioned on this site. Ill give them a go at just neck sizing and see what the results are.

I appreciate the replies as well

Haggs...

I know what you mean about neck tension with the lee collet die and neck tension. I've sanded most of my mandrels down a bit and also gotten some from lee that are .0015" undersized which makes my neck have the same tension as most fl dies.
The lee mandrel doesn't make a good expander in my opinion.
You should be able to take a measurement inside your case mouth after going throug the lee die. I would hope you can get it down to .275" after sizing....especially after annealing. You may have to gradually turn your die in just a hair to get there.
Another little trick with the collet sizer to make it a bit more aggressive is to hold your handle down a full 2 seconds when sizing....then turn the case 1/3 turn or so and give it another 2 second shot at sizing. It should help some with normal case spring back.
Let us know how this goes....I have lots of lee collet dies but very few sit in my inventory as they came from the factory. I wish they'd pack a slightly smaller mandrel in their dies right from the factory.

Just got my 1 & 2 thou undersized mandrels this past week. Went straight to the -2 mandrel. Bullet grip with the "stock" mandrel is pathetic.

Sometime the inside expander will drag the neck/shoulder
out a scosh. USE A Q-tip and lube a bit at the inside neck/shoulder. If you aren't using Imperial Die Lube get
some.

I would suggest that you seat the bullets .005 off the lands to touching the lands for a start, as long as they are not Barnes bullets.

keith.. that happens to bring up a totally new topic

i recently used the tubbs final finish system to try and clean up the factory barrel on the 270.. pushed the throat out almost .01

having trouble getting the bullets all the way out to the lands now while maintaining a decent .277 seating depth as many recommend. I am not too concerned with that as of now though, accuracy didnt change too much and i am looking to use this action soon for a full build including polishing raceway, truing lugs, bolt face, receiver face, luge etc... hopefully gonna put in an order for a shillen soon and then order a macmillan.

more so just concerned about the headspace varying on reloads.