PMA Blog

Case Trimming

Trimming the cartridge case to the proper length is a crucial step in case preparation that should not be overlooked or underestimated. The cartridge case or the rifle can be damaged, or even worse you get badly injured.
In most instances cases should be trimmed after firing and sizing. Trimming new brass is necessary for a lot of wildcats and can be beneficial in some instances, but by and large, trimming new brass is absolutely unnecessary. Cases should be trimmed after you have sized the case, because the expander ball on the decapping pin can (and will) stretch the neck. Those of us that neck size should get into the habit of trimming after sizing as well. This is a good rule of thumb to go by, and hopefully it will keep you safe during the reloading and shooting process.
There are so many case trimmers out there that work, deciding which one is right for you can be confusing. Even though I have trimmed thousands of cases, using about every method possible, I can’t answer the question of what case trimmer is right for you because of all the variables that may be involved. I can, however shed some light on the subject.
The two most popular designs of trimmers either index (1) off the base or the head of the case, (2) off the shoulder or datum line of the case. There are pros and cons to each and it all depends on what you are willing to live with.
Let’s talk about the first one I have listed, indexing off the base, or the head of the case. The pros to this method are that you can achieve a very accurate over all length and that is after all, what it is all about. The cons to this method are that you can get some variation doing it this way. Let me explain, the base is not always square to the body or can be damaged during firing especially if it is fired through a military style rifle with a very aggressive ejector. These cases should be discarded, but sometimes they can be overlooked. This condition can lead to an over all length that is incorrect. The case head being out of square will be corrected upon firing, however that case will wind up being shorter than the rest of your cases, possibly creating a difference in the neck tension on the bullet. The more you can do to eliminate variables in your reloads the better off you are going to be. This method can also be very slow, and if the user gets careless the result will be a inconsistent over all length.
The second method I mentioned, trimming off the shoulder or the datum line of the case, has its pros as well. I have found this to be the quickest of the methods and very accurate as well. After the case has been sized through the die the dimensions (particularly the headspace) of the cases are usually very uniform and exact, this allows the case to be trimmed by indexing off the shoulder. This method can be done very quickly, by hand, or by powering either the case, or the trimmer. You also don’t have to worry about the case heads being out of square with the body using this method. Generally the trimming time is cut in half, and this leads to greater focus on the job, without becoming careless.
The choice is yours to make. I hope that this was some help to you, weather you are looking for your first trimmer or looking to replace the trimmer you have. Just remember to always put safety first and accuracy second, and you will start making little bug holes in no time.

It’s been a long time since we’ve posted anything new here on the blog. I thought now was a good time to post an update on a few items of importance.

1) The Model B is in stock and ready to ship per your specifications. When you receive this neck turning tool it will be 95% ready to go. All you need to do is set the mandrel where you want it and get to turning.

2) Carbide Mandrels are nearly done! I estimate that we’ll have them in stock and ready to ship by September 14th, but it should be considerably sooner than that. The final cost projections came in under where I thought they would be so we were able to price them a little lower than I had even hoped. This was a little surprising considering the cost of carbide these days.

3) Our next serious project is the design of a big case trimmer. The design is in the final stages and we should begin serious prototyping this Fall. Before we introduce the big trimmer we will be offering a Strickland-style quick trimmer to fit in your range box. Modeled after the trimmer formerly made by Homer Strickland, this little guy is for those guys who like to give their brass a quick once over on length after sizing during a match. It’s not intended to be used to remove more than a couple thousandths.

That pretty much does it. We will send out a newsletter when the carbide mandrels are in stock.

Good shooting,

Pat

This post is to confirm that the auto-email feature works.

PMA Tool Model A Neck Turning Tool (March 8, 2011)

We have the neck turning tools in stock and I must say that they look and work even better than Matt and I had hoped. The updated photo of the tool will post Tuesday morning on the website. This will become your favorite neck turning tool the moment you use it. I will be adding them to the inventory tomorrow (Wednesday) and they will be shipping no later than Monday afternoon. Unfortunately, mandrels will still be a few more weeks before arriving.

We also finished the machine work and deburring of all of the powder measure parts this afternoon and they are at anodize as of 5 o’clock. The photo of these stands will be on the website just as soon as we can get them together.

As always, thanks for looking, and good shooting,

Pat

We’ve been plugging away at the Neck Turning Tool and we are nearly there. I anticipate them to be in stock by March 7th. The powder measure stand before the end of March and all of the neck turning accessories before mid-April.

I HATE case trimming with a passion, it is probably the only step in reloading that I dread doing. Matt and I are experimenting with a new trimmer design that could change the way you think about case trimming, I know it is starting to take the drudgery out for me. It’s not a revolutionary design by any stretch of the imagination, well I guess it might be. What it will end up being is a combination of several different concepts rolled into one affordable, quick and easy to use trimmer (with micro-adjust ability thrown in for good measure).

Check back on the website and the blog periodically in the coming weeks as we will be uploading some new photos and videos of our products in use as we complete them. We will also be starting our advertising campaign in earnest with advertisements, videos and write-ups in some of our favorite shooting forums and publications.

One last thing, if anyone is selling a PPC bolt face, light varmint RBLPRE Bat complete rifle, fire me an email with the details. I’d prefer a round or multiflat in a SB, B or 3Lug. I hope to finally shoot at the Super Shoot this year and I don’t have enough time to build one from scratch.

Thanks for looking,

Good Shooting,

Pat

Last night Matt and I met with two of our expert benchrest shooting friends to evaluate the cut finish on our sample brass and they were impressed. We will be going into production on the cutter within the next two weeks.

We are also putting some mid-production final touches on the tool itself. We are keeping our fingers crossed to be able to achieve our product release date of February 18th on this tool. Around that time we should also be able to start offering our own line of stainless mandrels (particularly our own spin on expanding mandrels) as well as the Free Floating Expander Die from our friends over at 21st Century Shooting. The Free Floating Expander Die will be available sooner.

Thanks for reading and Good Shooting,

Pat

We are running a little behind schedule on the introduction of our Model A neck turning tool. Right now we are in production on the body of the tool and should start with the balance of the parts very soon. We should be ready to have the tool ready for delivery late February.

Matt and I are working with some of our machine shop and tool grinding friends, finalizing the geometry of the cutter itself. We’ve been experimenting with several different new cutter designs of our own and neck tools from various manufacturers trying to find a design that results in quick, easy cutting with the finest finish possible.

Matt or I will keep you updated on our progress.

Thanks for reading and good shooting,

Pat

We at PMA Tool would like to welcome you to our blog. We will be using this forum to post updates on new products we are developing and shooting events we will be attending. We might also share some personal shooting or hunting stories and might even share some opinions on the goings on of the world.

We hope to have a personal relationship with our customers and want to cater to your needs. If there is a need for a product out there you’d like to see us make or someone’s product you’d like to see us carry, drop us a line on the blog or email me at patr@pma tool.com. We are ALWAYS open to suggestions.

Thanks for reading, and good shooting,

Pat