peterk1234 Posted August 27, 2017 Share Posted August 27, 2017 Well, my wife is a proud owner of a new STI Apeiro. We put a few hundred rounds through it and I had some interesting issues pop up. First, we went from a very light trigger pull when unloaded to one of about 50lbs with a mag in it. I was pissed. After some tinkering, I figured out it was the over travel screw on the trigger. Half a turn solved the problem. The mag must be pushing on something when inserted. All good. Second issue was we had a number of times when the gun would not go completely into battery. The slide would stop with just an 1/8 of inch more to go. No amount of pushing was going help. So, today when we shot it, we immediately grabbed the bullet. I pulled the gun apart and did a plunk test. Bullet would not seat all the way into the chamber. This particular bullet was one of my reloads. I was not sure if it was a length issue or a crimp, so I needed to get back to the house with my reloading gear to figure it out. The weird thing is, I put the same bullet in the Marauder, and bang; no problem. Back at home I figured out it was length. I go for an OAL of 1.135 usually and I need to get down around 1.120 for it to plunk cleanly. So the base of my bullet must have been getting into the rifling is my guess. No biggie, problem solved. Anyone else ever have an issue with length like this? I am within spec at 1.135, so I guess I am surprised. Last issue is feeding. It would happen with factory and reloads, although definitely more issues with my reloads. I use coated cone bullets. Now if I take one bullet in the mag and manually point the bullet up just a tiny bit before loading, it slides right into the chamber. Again, never an issue with the marauder. Is this just a tighter gun and I have to break it in for a while, or is this why people are purchasing the hundred dollar mag tuning kits? Thank you Pete Link to comment Share on other sites More sharing options...
raz-0 Posted August 27, 2017 Share Posted August 27, 2017 Only time I have had issues with .40 at 1.135 is with a barrel that was supposedly finish chambered but was not, or has been done incorrectly. A number of thing can cause feeding issues. Check your feed lip dimensions and make sure the bullets aren't dragging on the front as they feed. Link to comment Share on other sites More sharing options...
BigGabe Posted August 28, 2017 Share Posted August 28, 2017 I had a problem with a round occasionally not wanting to chamber. Had to push it closed the last little bit. Just reloads though. Come to find out the chamber was at minimum length dimensions and some of the cases were just a hair too long. Factory would run all day, no problems. Lengthened the chamber a few thousands and it's been fine ever since. Link to comment Share on other sites More sharing options...
MrPostman Posted August 29, 2017 Share Posted August 29, 2017 Well, my wife is a proud owner of a new STI Apeiro. We put a few hundred rounds through it and I had some interesting issues pop up. First, we went from a very light trigger pull when unloaded to one of about 50lbs with a mag in it. I was pissed. After some tinkering, I figured out it was the over travel screw on the trigger. Half a turn solved the problem. The mag must be pushing on something when inserted. All good. Second issue was we had a number of times when the gun would not go completely into battery. The slide would stop with just an 1/8 of inch more to go. No amount of pushing was going help. So, today when we shot it, we immediately grabbed the bullet. I pulled the gun apart and did a plunk test. Bullet would not seat all the way into the chamber. This particular bullet was one of my reloads. I was not sure if it was a length issue or a crimp, so I needed to get back to the house with my reloading gear to figure it out. The weird thing is, I put the same bullet in the Marauder, and bang; no problem. Back at home I figured out it was length. I go for an OAL of 1.135 usually and I need to get down around 1.120 for it to plunk cleanly. So the base of my bullet must have been getting into the rifling is my guess. No biggie, problem solved. Anyone else ever have an issue with length like this? I am within spec at 1.135, so I guess I am surprised. Last issue is feeding. It would happen with factory and reloads, although definitely more issues with my reloads. I use coated cone bullets. Now if I take one bullet in the mag and manually point the bullet up just a tiny bit before loading, it slides right into the chamber. Again, never an issue with the marauder. Is this just a tighter gun and I have to break it in for a while, or is this why people are purchasing the hundred dollar mag tuning kits? Thank you Pete The first problem you described about the trigger pull can be caused by a magazine that is bowed out in the front, the trigger bar will hit the magazine before the sear clears the hammer hooks keeping the hammer from falling. To verify this is indeed happening you will want to get a few mags and insert each one, if it only does it with the one mag then you can fix it by using a brass hammer to hammer it back into spec on the front. I have done this and it is an easy fix. Second issue on FTF may or may not be a chamber issue, it could be the coated bullet or the actual length of the round. I have seen coated bullets that were a few thousands larger in diameter and would not chamber in some guns but work fine in others. Check diameter of bullet first with a good digital caliper, also check length of rounds sticking as they may actually be longer due to variances in progressive press loading with mixed headstamp brass. If these tests do not reveal the problem then pull both barrels (Maurader and the new one)out and compare chambers on both. You will be able to see a difference if there is one in the throat area, take a sized piece of brass and insert into the chamber on each barrel, if the Marauder barrel allows the brass case to seat deeper then the chamber on the new barrel is too short and will need to be recut to the correct depth. Last issue is most definitely a magazine issue, you will need to tune the feedlips. On a .40 s&w you will need the lips to be .380"-.385" wide (inside measurement)at the front closest to the chamber with mag inserted and .005"-.008" less at the rear so the bullet is tilted upwards slightly in the mag. Sent from my SAMSUNG-SM-G935A using Tapatalk Link to comment Share on other sites More sharing options...
MikieM Posted August 29, 2017 Share Posted August 29, 2017 (edited) Assuming this is a .40 S&W, check the bullet crimp. If you are having to crimp down to the .420/.421 mark, then your chamber may be too tight and anything larger is sticking. SAAMI specs are .423 inches at the case mouth. It's an easy fix, and usually one that can be done locally. Regardless, accuracy and safety should not be affected. Edited August 29, 2017 by MikieM Link to comment Share on other sites More sharing options...
TCB Posted August 29, 2017 Share Posted August 29, 2017 I had similar issues with my Cameron's 2011. I called him and he said he built it to run jacked ammo only (for the guy who had it built) and that my coated bullets would not work unless he "lead reamed" it... Link to comment Share on other sites More sharing options...
peterk1234 Posted August 31, 2017 Author Share Posted August 31, 2017 Thank you for the comments guys. Trigger has been 100% spot on now that the over travel screw is adjusted. I am down to almost zero feed issues now as well because of the slight OAL adjustment to my loads. I ordered a tuning kit, so I will be tweaking the mags though. With the OAL change, I only had two battery issues out of 400 rounds. So now it appears that it is coming down to properly sizing my brass at the extractor end. I am not sure I can get to 100% with refired and tapered brass (9mm). Worst case, I will talk to STI to determine if the chamber should be reamed a bit, but I will fire another 500 or so rounds through it to see what happens. Pete Link to comment Share on other sites More sharing options...
assaulter Posted August 31, 2017 Share Posted August 31, 2017 My edge has a tight chamber and doesn't like lead bullets. When I talked to STI they told me to just use jacketed. In other words, no help given. Link to comment Share on other sites More sharing options...
StuckinMS Posted September 1, 2017 Share Posted September 1, 2017 Coated bullets are almost always restriked after the coating is applied. I have gotten batches that were supposed to be .400 and were actually .4015 and sent them back they acknowledged the restriking dies had worn out and they fixed them and sent them back to me. Problem solved. Other issues could be mags like previously stated. Link to comment Share on other sites More sharing options...
peterk1234 Posted September 7, 2017 Author Share Posted September 7, 2017 Got the tuning kit yesterday. Took a a digital caliper to my mags.....wow. Rear wider than the front on most and way wider than they should be. They have always functioned fine in our Marauder so I wasn't expecting much. So I banged the crap out of them (that was daunting), then sized them. Took the fine file and took out any burrs and roughness in the lips, then took 800 grit paper and worked the lips even more. Threw the mags into my tumbler for a few hours, then waxed the inside of the mags. I even buffed the followers. Huge difference in the Apeiro. Wow. Link to comment Share on other sites More sharing options...
StuckinMS Posted September 9, 2017 Share Posted September 9, 2017 Now that sounds like a full service tune job! Never thought about tumbling them Link to comment Share on other sites More sharing options...
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