Re: Problems with brass
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: s.i.t.</div><div class="ubbcode-body">I borrowed the micrometer from an f class shooter who gives classes on reloading once a year. He taught us to use a case fire formed to our chamber, put it in the mic to find the the shoulder depth, and adjust the fl sizing die to 1-2 thousandths shorted than the chambers shoulder. As soon as my fte brake is in I've already notified my smith of the problem and he's gonna check my head space for me when I bring him the the rifle. </div></div>
You have posted multiple problems. First your "F class shooter" is a poor reloading teacher for not teaching you the best way to know with certainty is to measure then measure again and then to <span style="font-weight: bold">write it down</span>. You cannot reliably make an assumption about where you are with the case shoulder datum line then guess at an adjustment and expect good repeatable results. You need to have good tools. These tools are not just the bits of hardware needed but also include basic knowledge of the loading process too.
More than likely based what you have posted you are creating a headspace problem by oversizing and pushing the case shoulder back too far which leads as you have found to very short case life and case failures. This can be dangerous.
The "F class shooter" who allegedly teaches reloading once a year aside the heart of the problem is that you are working blind with no precision tools in hand to measure the RESULTS of what you are doing to your cases when you are full length sizing.
But this is just the start you also need to beg borrow or steal and read cover to cover twice at least two good recently published books on reloading. If you can borrow some books on handloading you probably have found a resource with some experience that can help you. Don't be shy, ask as many stupid questions as the person will tolerate and be sure to supply beverages and snacks so they come back when you want more help.
Many of the old now classic reloading books make a lot of assumptions (like your F class shooter may have made) and do not teach use of common inexpensive reloading measurement tools widely available today. Don't buy the classics until you are successfully loading accurate ammo. A reloading manual from a powder or bullet maker does not count you need a book on the why and how to produce good reliable safe handloads. If you borrow reloading books take lots of notes and make drawings so you can develop an understanding of the process and have a guide you can refer to during the process of handloading. Most people develop a loading workflow based on their shooting needs type of press they use space etc. You will too over time as you gain experience on your loading bench and good notes will come in handy as you develop your own handloading workflow.
If you buy new books be sure to get a good look at them before you buy to make sure they include the use of headspace and bullet measurement tools. There are obviously many methods out there but these tools are relatively inexpensive and provide the user with very reliable information that will keep you out of trouble and help you to shrink your group sizes. Precision at 100 yards starts with high precision on your loading bench.
Stop guessing. You will need at least one pair of calipers and a 1" micrometer and if you are using bushing dies a ball micrometer. Buy at least one set of good calipers that can deliver 0.001" measurements with 0.0005" precision, look for this in the caliper's spec sheet. If it is not on the spec sheet or there is no spec sheet keep looking. I like direct read digital calipers for comparator use as you will know at a glance where you are while working at the press.
You will also need parts to assemble a headspace and bullet comparator. Strictly speaking you don't really need the anvil but it adds to repeatability in measurement. Buy the bullet comparator insert with the other stuff to save the usual $5 shipping charges on a $4 part. The bullet comparator insert will come in very handy very soon so buy it up front.
I cannot recommend the comparator kits with many extra inserts unless you happen to need a lot of the included inserts as it costs less to buy just what you need. For example .308Win, Hornady LnL comparator body #B2000 @ $17.00, LnL anvil #AB1 @ $14.00, LnL .30cal bullet insert #830@ $4.00, LnL headspace insert #D400 @ $8.00 for a total of about $45 give or take depending on vendor. Sinclair also makes similar tools to make similar measurements but they cost a bit more.
It is very unlikely your gunsmith will find anything wrong with the rifle chamber. More than likely he will use go-no-go gauges and find the chamber is within SAAMI specs. But it won't hurt and you will never know without guess what, measurement tools!
Hope this helps!
