Light Strikes

cds43016

Member
Joined
Apr 7, 2016
Messages
133
Reaction score
50
Location
KY
I’ve been having a problem with light strikes with my 686. It started when I began loading on my Hornady LNL AP Press. I used Starline Brass and CCI 500 Primers. I get a light strike about 1 in 100 rounds. They all have went off on the second hit. This tells me that they are not seated deep enough although they are all seated at least flush. I check every loaded round. I’ve used this combination of brass and primers for over 10,000 rounds using a RCBS Bench Mounted Priming tool without a hitch. It’s not the gun.

I called Hornady and they told me the press is designed to seat the primers flush or a little below and didn’t have a solution if they are seated at least flush. It is within design spec. This is not much help.

I checked the obvious in making sure the primer seater plug is tight to the shell plate and make sure I give a firm press to the handle to seat the primer. I did internet searches and some people have glued washers under the primer seater plug on the press body to push it in further or added material to the seater stem itself.

Any ideas?
 
Register to hide this ad
This is interesting because I have also had light strikes with my 686, using a Hornady LnL and CCI primers.

However, I've have visually inspected all of my rounds and the primers were fully seated. I also have shot several hundred rounds thru other guns and never had a problem. Mine is a 686 Perf Center, and I had 5-6 FTF in about 200 rounds fired, so I figured maybe they weakened the spring a bit while tuning it, but the trigger is heavy enough that should not be the problem. I'm going to try a Apex XP firing pin to see if it helps.
 
There was a thread a while ago called "lite hit". Ashlander commented about slow D/A trigger pull on a newer gun. I found this to be my problem with my 686. I sped up the D/A trigger pull just a bit and all of my lite strikes went away. I was getting 2 or 3 in a row at times.
 
I find the light hits to be an excellent means of ball and dummy practice the light hits are always unexpected and since I am usually just shooting targets the duds are of no consequence other that providing another learning experience for me.
 
Could be from lots of things.....

Dies not tight.
Primer not seated 100%
Spring screw loose, causing weak hit.
Short or damaged firing pin.
cylinder or pistol head space off.
Plain old hard CCI primers..............

Yes, soft Federal primers might fix the problem.....
but if not you need to start weeding out the problems.

Good luck.
 
I'd check the gun, first, and then the primers. I had a couple boxes of CCI that would occasionally misfire in DA in my Target Masterpiece--but nothing else. I was switching over to Winchester anyway to take advantage of a HazMat deal, so I just used those for .38 and used CCIs in 9mm only.

Have you switched from one lot of primers to another lately?
 
I stopped using CCI 500 primers awhile ago due to light strikes and/or duds in my M&P 9. I've reloaded thousands of rounds using CCI's and yup, same here, about 1 in every 100 wouldn't go off. I've since switched to Winchester WSP primers and now have 100% success using them.
 
The last 400 rounds I loaded I went back to the RCBS Bench Primer instead of using the priming on the LNL AP Press to make sure it was not the gun. Not a single problem just like the 10,000 rounds primed before that using the RCBS Bench Primer. It seems that the LNL AP press does not seat the primers as deep. The fact that they go off on the second hit points to this even though they are flush. I need to get them slightly below flush. I’m not sure how to do that. The RCBS Bench Primer has a much better feel for primer seating than the LNL AP and rounds primed with it look and feel to have the primer seated deeper.

Using the RCBS Bench Primer is an extra step and takes away some of the advantages of a progressive press. For years I primed off the press before the LNL AP for various reasons, but I was hoping this time it would be different. When I shot in matches a FTF for any reason was just unacceptable. I guess I still have that mentality. Even 1 in 100 is 1 to many.

I thought about using another primer brand. I understand CCI primers are harder but never had a problem until now. Maybe a different brand would be better on the LNL AP but I have over 9,000 CCI primers.

Indeed, a dud is learning experience. It is unexpected and does show any faults in form. You just have to take a moment to be sure it not a hang fire.
 
Are you using new Starline brass? I have seen this before with my LnL's. Once the new brass has seen a primer it seems to seat fine but that first go around, some just don't fully seat on the LnL. I've only experienced this with brand new Starline, nothing else. I can usually feel the primer not seating and pop that piece out and seat the primer on my little RCBS press. Should mention I use Winchester primers.

Stu
 
Last edited:
I've had light hits in an S&W M&P .45 which I traced to the primers not being fully seated, along with the CCI primers I was using. CCIs are known to be hard. I've even had issues with CCI in .35 Remington reloads used in a Marlin 336.

Solving this problem caused me to pay greater attention to the primer pocket. Large pockets get uniformed with the appropriate tool while small pockets don't require uniforming in my experience. Uniforming the pockets insures that each and every primer is seated properly. You can feel the difference in the amount of resistance felt when seating the primers.

As I'm no longer a competition shooter, I don't lose any sleep worrying about which primer just might shave a hundredth of an inch off my group.
 
Last edited:
Primers have to be seated all the way into the pocket. If they do not bottom out then the first strike only seats them (then some call it a "light" strike) after the primer is fully seated in the pocket then the next blow will fire it.
Seating the primer "at least flush" is not fully seating the primer and could lead to the dreaded "light strike".
This is common with progressive loaders...adjust primer seating depth or go to hand priming off the press.
Gary
 
I have a 19 -5 going in to the gunsmith today for light strikes. I will report on the findings.
 
Primers have to be seated all the way into the pocket. If they do not bottom out then the first strike only seats them (then some call it a "light" strike) after the primer is fully seated in the pocket then the next blow will fire it.
Seating the primer "at least flush" is not fully seating the primer and could lead to the dreaded "light strike".
This is common with progressive loaders...adjust primer seating depth or go to hand priming off the press.
Gary

I believe this is exactly the problem. The LNL AP does not seat them deep enough. If I hand prime, then the success rate is 100% with the CCI Primers and Starline brass (it’s not new brass, it has been reloaded many times). I can control the seating depth easily by hand priming and can be sure they are seated below flush.

Hornady says there is no way to adjust the depth and if it’s flush it’s within spec. The primer just needs to go a bit deeper. I’m trying to see the best way to do that. Based on some other forums, some people have glued washers on the press body under the primer seater plug to make it go deeper. Some have tried making the seating punch longer. These solutions have met with limited success. I’m looking for some other ideas.

Maybe another primer brand would work better and is the only solution if I want to prime reliably on the press. I just have so many CCI primers and they are generally the easiest and cheapest to find.
 
Last edited:
Me, too

On my last 2 trips to the range, I've had 2 "light strikes" (1 on each trip) with CCI SPP. The 1st one was 45acp - small primer; the 2nd was 9mm. Except neither of them fired on 2nd attempts, or 3rd or 4th..... They just wouldn't fire. I only have a couple years loading experience, maybe 7-8000 rounds, but I guess it happens.
 
Heavy Trigger??

This is interesting because I have also had light strikes with my 686, using a Hornady LnL and CCI primers.

However, I've have visually inspected all of my rounds and the primers were fully seated. I also have shot several hundred rounds thru other guns and never had a problem. Mine is a 686 Perf Center, and I had 5-6 FTF in about 200 rounds fired, so I figured maybe they weakened the spring a bit while tuning it, but the trigger is heavy enough that should not be the problem. I'm going to try a Apex XP firing pin to see if it helps.

A "heavy" trigger is only indirectly related to how hard the hammer/firing pin hit the primer. You are compressing two springs in DA mode, the hammer spring and the rebound slide spring. Only the hammer spring stores energy and releases it into the hammer fall. The rebound spring does nothing except reset the action when you release the trigger. It's awfully easy to ease off the hammer spring strain screw and achieve a really light DA pull that doesn't hit the primer hard enough. A heavy SA pull means the SA notch is cut deep and will feel heavy with any spring setup.
 
A "heavy" trigger is only indirectly related to how hard the hammer/firing pin hit the primer. You are compressing two springs in DA mode, the hammer spring and the rebound slide spring. Only the hammer spring stores energy and releases it into the hammer fall. The rebound spring does nothing except reset the action when you release the trigger. It's awfully easy to ease off the hammer spring strain screw and achieve a really light DA pull that doesn't hit the primer hard enough. A heavy SA pull means the SA notch is cut deep and will feel heavy with any spring setup.

Read it again, 1 of 100, fired the 2nd time, not the gun.
The priming system on the lnl, like the 550, is not ideal. Primers need to seat in the bottom of the pocket, not flush with the case head, push harder! It is almost impossible to have a primer go off seating it properly. Mine all look a little flat, yes I push that hard. I never get a ftf on a primer, even cci n a glock.
 
Last edited:

Latest posts

Back
Top