dauntedfuture

I have several different brands of 55 SPs spin apart out of 20" 1-7 barrels. Hornady SXSPs have an especially thin jacket. Do what ever you want but when they spin apart, I told you so. I have some other match 53g HPs that will also spin apart too out of a 1-8" 18" If you look onto some of the compay web sites they will reccomend twists and velocities for their bullets best accuracy, some will have a little more information. If you shoot almost any bullet too fast it will come apart.

I have a 16" rifle gas Micro MOA barrel and have had zero issues with it. There are no undergas issues that i see. Im running an adustable JP gas block and its not quite fully open with plastic TACCOM buffer and Lightweight BCG.

You need to pay attention to the intended use and loading of the bullets that you choose. 75 AMAX and almost all bullets over 77g are not intended for magazine length use. When you look in a loading book for a 75 amax or an 80g SMK etc. you will see that the OALs exceed magazine length. Likewise, there is little to no benefit in loading lond bullets that are intended to be shot from a magazine length like the 77g SMK, 77SMK, 75 hornady BTHP etc. 77 TMK and SMKs shoot so well loaded to mag length there is not a reason to try and load them long.

Mine came with only one moon clip and 12+ DA pull. There was no indication that there is or was anything "custom shop" about this pistol. Complete with some tool marks and rough guts too...

your 1/7 barrel has nothing to do with how soft or cheep you can reload for it. You should limit yourself to not shoot light weight HP or SP bullets 55 or less as they will be more likely to come apart upon exiting the muzzle. These disentigrating bullets might however be soft shooting and cheep.

What you are describing is what happens when you are resizing mixed range brass and your FL dies are not set up correctly. In reality, i suspect that you are not sizing the cases enough if you are getting 20% that dont pass the guage. Those 80% that are passing were likely shot in a tighter chamber and as such the shoulder is not really getting set back. In many cases you have to cam over your FL dies. You might even have to take a little off the bottom of your fl die or get another FL die. A SB die will not help with setting back the shoulder, a SB die just sizes the base a little smaller. To fix, find 10 sticks of brass that dont guage and keep adjusting your dies until they do. Do not size a piece of brass more then once, each time you adjust use a "new" piece of fired brass. When you think its all set, size and test another 10 sticks. In an AR you can NS brass. The bolt on an AR also has enough momentum to size your brass in the chamber sometimes, extracting it is another issue.

I have had real good luck with TAC and 77's in several rifles and 24.2 is my go to load these days. I use the same 24.2 for all bullets (50-77) so i dont have to adjust the powder measure.

find a published load in a book when loading shotguns

Different makes of the same weight bullet produce different pressure and velocity numbers. The shapes of the bullet will also effect pressure and velocity. All things equal, a bullet with a thicker jacket will produce higher pressures then a thinner jacketed bullet. In an extreme case a solid copper bullet will produce more pressure by a wide margin. Reloading books serve as a guide for reloading. In some cases you can put well over a books max charge in a case and have sub max chamber pressure. Long throats and seating bullets out effectivley reduce pressures for a given charge. Barrels that are worn will require a little more powder to maintain velocity then when they were new. When you are reloading for a bolt gun the first sign of pressure that you usually run into is a stickey bolt. In a semi auto you normally start to see marks from an extractor. Looking at a primer is a universally poor way of evaluating pressure, you have to look at the brass, feel the bolt lift/ look for marks as well as evaluate velocity over a cronograph. Also consider some lots of powder are faster or slower then others, Varget is natorious for this. With a 20" .308 your going to have trouble maintaining a supersonic past 800 yds at best so dont push it. If its a remington rifle then your bullets are probably seated out long. If the rifle is still shooting 1.75" or so i might try another bullet and see what happens, the 155's just might not work as they dont like to jump and if you are seating them out so there is bearley any bullet left in the case then that will not help anything at all. A Sierra 175 is a good place to start and they are not sensitive to jump.

Try the levang comp. I have a used one if you cant find one.

Provided that there is not an issue with the gas key hitting the BCG i would try another bolt with the same BCG that you are using and see what happens. On my last build i had to swap out the new coated bolt with an older one to get things running. I suspect but i dont know, that the new high speed coated bolt is a little on the big or stiff side of things.

7.65 Tokarev (the most powerful handgun ctg in the world according to that Russan cop in Red Heat.), .44 Mag (the most powerful handgun ctg. in the world - Dirty Harry) and whatever caliber hell-Boys revolver is, 4 bore i think....

You might want to check the twist on the barrels. I believe that some of the slower twist barrels are unreliable with 147g bullets. If the same loads work in that factory M&P barrel then thats a possible culprit. Too much crimp can upset things as well as a lee U die. I have been running all kinds of 147g bullets in a M&P 5" without issue.

You might want to try some proper jacketed bullets as well. I think you might find that you will get a little more smoke then you want with HS6 and BBI bullets.

I don't know what kind of accuracy you are looking for or expecting but I know a 3 rd group will not provide much information. it looks like you found something that might work. go and shoot 10 rounds and see what happens.

Hornady dies run on the smaller side for their standard dies. I also like the hornady lock ring design and the egg shaped expander ball. Of the dies i have i have yet to break a hornady decapping pin.

You really need to look at the crono data and see what kind of ES you are getting. A single 5 shot group can inform you of potential or at least tell you if a load is NOT going to shoot, its harder to evaluate what is best. Without knowing about your rifle and glass its hard to tell but if it was be i would just load 25g and go for it and call load testing a day. If you compare some of the lateral groups its about the same as some of the vertical on other groups. I might suggest that a 10 shot group would have rounded out all of the groups so that the vertical and horizontal are about the same. Also consider that wind effects horizontal groups and velocity variations effect vertical groups. Provided you are shooitng in an AR and that you are shooting 69SMKs, just seat them to magazine length, they are not going to shoot better seated out or if they do its negligible.

I have shot some of the 77 TMKs loaded to mag length. The BC of this bullet is about .420 which is the same as the sierra 80. Provided you are going to load long then you are better off looking at another bullet like the sierra 80 or some of the other real slick bullets like the Bergers or the JLKs. The advantage the 77 TMK provides is that you can load a .420 BC bullet to magazine length. I suspect that loading a 77 TMK long will yeild little real advantage over a mag length bullet under an objective 10 round test. You will be able to fit more powder in the case and get slightly higher velocity. This bullet was designed for mag length, load and shoot them that way and be happy. So far they have shot well in several rifles and all i did was swap out bullets.

"The case volume of a military case can be lower due to thicker walls, this causes higher pressures which can be dangerous if you load near the maximum loads. Measure case capacity (with water for example) and see for yourself." Not true. Most LC cases have the same or more capacity then commercial cases when talking 5.56. 7.62 cases are another story as they do have less capacity. As always work up etc. There is NOT a practical difference between .223 and 5.56 in practical terms other then the increased PSI spec for 5.56 vs .223. Some .223 reamers are bigger then 5.56 and some 5.56 are smaller then .223. Free bore in the throat area is another practical matter. Since most of us dont have a pressure guage at home i might suggest that many shooters are loading hot ".223" ammo that is in excess of 5.56 pressures especially when you are talking 80-90g bullets.

147 ball bullets are 2-4 MOA bullets. So... about 150 yds. assuming 4 MOA and you are dead nuts center on each shot. What you are going to find with ball bullets is that if you shoot a 10 shot group you will find 3-5 that are real close, its the other 7-5 that you are worried about and you cant cherry pick for the group.

Headspace on a rifle is a fixed distance and its from your bolt face to a measurement about 1/2 in the shoulder of the case. When you are talking about sizing cases, you are not adjusting headspace, your just sizing your brass more or less. Specific to your issue; most double feeds are caused by bad magazines so i would start there. If you are getting a double feed then that means that two loaded rounds are attempting to chamber at the same time. If you have a fired case and a live round then thats a failure to extract (if the fired case is stuck in the chamber) or a failure to eject (fired case and live round fighting to get into the chamber). Using the Hornade guage gives you a measureing point as a reference; your rifles "headspace" is NOT 1.459, thats just a reference. To answer your question you want to size cases that have been fired in your rifle to -.002-.003. I emphasise that you have to use cases fired in your rifle. An alternative is size a case and try to chamber and eject it using a "new" fired from your rifle case each time and stop screwing the die down when things work. From there size 5 and try them all. Then try some random cases and see if the all work. Your "headspace" on the loaded round shrinks because there is enough force to size the case when you slam the bolt closed. In a bolt action rifle it would be hard to close and you can gaul the lugs. Properly adjusting/ setting up your dies will primarily influence function of the rifle and or case life. Excessive sizing can reduce case life. In general, as long as all cases are sized the same you will not see an effect on accuracy. Cases that are not sized enough can also stick in the chamber, resulting in extractor marks that will mimic signs of high pressure as well. Without getting into the weeds; set your dies up properly, FL size your brass and go shoot.

I think most all FN guys at shooting fn Ar15 s now that fun makes them.

Dirty pistol brass and dirty rifle brass are different animals. With really clean or new pistol brass the expander will stick inside the brass a little. With rifle brass you are sizing the case, not expanding. With all rifle brass I have ever loaded the cleaner the brass the less lube you need. Its also quicker to tumble lube off clean brass then or lube off loaded ammo that has real clean brass.

It is often the case that the OAL of a case will shrink a little after you shoot it and grow after you size it. Im sure you are trimming after you FL size, correct.

its already been said but I don't think you will have any issue necking up 6.5x284 brass at all.