Primer depth with Dillon 550B

Steve Smith · September 12, 2000, 04:35 PM

How do you adjust primer depth? All my primers on my .45 acp come out flush, and I've been using them with no problems. However, I'm going to start loading .308 for my new M1A, and since it has a floating firing pin, I've been told to recess the primers a couple of thousands...how do I do that?

**Bud Helms** · September 12, 2000, 04:45 PM

Frontsight!,

Primers should be seated to the depth of the primer pocket, i.e., bottomed out. 'Don't want one to shift forward in the pocket when struck. That's a way to get a misfire, slight though it may seem, depending on how tight (or loose)the pocket holds the primer cup.

Even a floating, rebounding firing pin should have no problem reaching the primer.

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>... since it has a floating firing pin, I've been told to recess the primers a couple of thousands... [/quote]

Were you given a reason for it?

[This message has been edited by sensop (edited September 12, 2000).]

B9mmHP · September 12, 2000, 05:04 PM

Frontsight. Use a primer pocket reamer to make sure all the pockets are uniform,it wont make them any deaper unless they need it. then use a hand-held priming tool, and seat them all uniform, "Preasure" but dont crush them, you can tell when they seat.

As sensop said were you given a reason?

I have an M14 308, never heard anything about that.

------------------
"Defiance"
And yet...it moves
(Galileo Galilie)

"Spay or Nuter your Socialist Pets"

Steve Smith · September 12, 2000, 05:06 PM

The reason is that (on an M14), the firing pin hits the primer when the round is champered...deep seating the primer lessens the chance of the primer being hit hard enough to slam fire. Supposedly, if you load a round, then eject it, you'll see a dent where the firing pin lightly hit the primer.

[This message has been edited by Frontsight! (edited September 12, 2000).]

Nukem · September 12, 2000, 07:08 PM

Seat them where they belong, at the bottom of the pocket. Any more and you are crushing the pellet. The AR has a floating firing pin also, it's no big deal.

**Bud Helms** · September 12, 2000, 08:50 PM

...

[This message has been edited by sensop (edited September 12, 2000).]

**Bud Helms** · September 12, 2000, 08:53 PM

Frontsight!,

The firing pin return spring is strong enough to resist (prevent) return-to-battery firing pin bounce (to the degree it would cause a slam fire).

char923 · September 12, 2000, 10:01 PM

Frontsight
If you take your press with out primers and cases and push the handle forward you will see that the primer seating punch, will seat the primer to max depth. B9mmhp is right the problem would be in your primer pockets.

El Rojo · September 13, 2000, 02:20 PM

Man Frontsight, you are all over the Firing Line with these M1A questions! That is good though, we are all glad to help each other out.

I just seat the primer where they lay. It sounds like we have the same set up: M1A, Dillon 550B. Just put em in there and don't sweat that stuff. You have other things to worry about like whether there is powder in the case or not. Just inspect the primer to make sure it is flush or even a tad bit lower than the bottom of the case. The other 550B hangup you need to watch for is to check the plunger that pushes the primer up into the case. Sometimes powder or other junk gets on top of it or in between the plunger and the primer. You will start to notice dents and if it is even a slim little shiver of brass, lines in your primers. I put my handl forward every once in a while with no case or primer on the plunger and wipe it off.

Steve Smith · September 13, 2000, 03:19 PM

Yeah, I'm all over a couple of other sites, too!

Sensop,
There is no primer return spring on an M14, and I was warned about this with an American Rifleman article that was includedin the paperwork from Springfield.

johnwill · September 14, 2000, 08:18 PM

The Dillon 550B will seat the primers properly. If there is some reason you really want them recessed, the proper way would be to ream the pocket deeper. Let me be quick to state that I see no reason for that. I've loaded tons of .223 with my Dillon with no primer problems. If you're really worried about the primers, go with a harder primer. I use CCI in the .223, they're one of the harder primers available.

Patrick Graham · September 16, 2000, 10:10 AM

You can adjust the primer seating depth on the 550 by moving it out from the edge of the reloading bench. If you upgraded your RL550 to a RL550B you had to move the press out away from the edge of the bench by about 1/8 - 1/4 inch to accomidate the charge bar return plate thickness.

B9mmHP · September 17, 2000, 05:53 PM

Frontsight: You are right about the slam fire.
I have done some reasearch on that and found a couple things. But I still recomend the primer pocket reamer.
#1 You can have a slam fire if you use the wrong primers.( Soft Primer ) One recomends CCI primers. Another #34 primer did`nt remember the Mfg.
#2 You can ream the pocket deeper, but that can weaken the case.

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September 12, 2000, 04:35 PM	#1
Steve Smith Senior Member Join Date: December 9, 1999 Posts: 4,131	How do you adjust primer depth? All my primers on my .45 acp come out flush, and I've been using them with no problems. However, I'm going to start loading .308 for my new M1A, and since it has a floating firing pin, I've been told to recess the primers a couple of thousands...how do I do that?

September 12, 2000, 04:45 PM	#2
Bud Helms Senior Member Join Date: December 31, 1999 Location: Middle Georgia, USA Posts: 13,198	Frontsight!, Primers should be seated to the depth of the primer pocket, i.e., bottomed out. 'Don't want one to shift forward in the pocket when struck. That's a way to get a misfire, slight though it may seem, depending on how tight (or loose)the pocket holds the primer cup. Even a floating, rebounding firing pin should have no problem reaching the primer. <BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>... since it has a floating firing pin, I've been told to recess the primers a couple of thousands... [/quote] Were you given a reason for it? [This message has been edited by sensop (edited September 12, 2000).]

September 12, 2000, 05:04 PM	#3
B9mmHP Senior Member Join Date: February 2, 2000 Location: Texas Posts: 465	Frontsight. Use a primer pocket reamer to make sure all the pockets are uniform,it wont make them any deaper unless they need it. then use a hand-held priming tool, and seat them all uniform, "Preasure" but dont crush them, you can tell when they seat. As sensop said were you given a reason? I have an M14 308, never heard anything about that. ------------------ "Defiance" And yet...it moves (Galileo Galilie) "Spay or Nuter your Socialist Pets"

September 12, 2000, 05:06 PM	#4
Steve Smith Senior Member Join Date: December 9, 1999 Posts: 4,131	The reason is that (on an M14), the firing pin hits the primer when the round is champered...deep seating the primer lessens the chance of the primer being hit hard enough to slam fire. Supposedly, if you load a round, then eject it, you'll see a dent where the firing pin lightly hit the primer. [This message has been edited by Frontsight! (edited September 12, 2000).]

September 12, 2000, 07:08 PM	#5
Nukem Senior Member Join Date: January 29, 2000 Posts: 709	Seat them where they belong, at the bottom of the pocket. Any more and you are crushing the pellet. The AR has a floating firing pin also, it's no big deal.

September 12, 2000, 08:50 PM	#6
Bud Helms Senior Member Join Date: December 31, 1999 Location: Middle Georgia, USA Posts: 13,198	... [This message has been edited by sensop (edited September 12, 2000).]

September 12, 2000, 08:53 PM	#7
Bud Helms Senior Member Join Date: December 31, 1999 Location: Middle Georgia, USA Posts: 13,198	Frontsight!, The firing pin return spring is strong enough to resist (prevent) return-to-battery firing pin bounce (to the degree it would cause a slam fire).

September 12, 2000, 10:01 PM	#8
char923 Senior Member Join Date: February 18, 2000 Location: Anchorage AK Posts: 237	Frontsight If you take your press with out primers and cases and push the handle forward you will see that the primer seating punch, will seat the primer to max depth. B9mmhp is right the problem would be in your primer pockets.

September 13, 2000, 02:20 PM	#9
El Rojo Senior Member Join Date: February 4, 2000 Location: People's Republik of Kalifornia Posts: 2,057	Man Frontsight, you are all over the Firing Line with these M1A questions! That is good though, we are all glad to help each other out. I just seat the primer where they lay. It sounds like we have the same set up: M1A, Dillon 550B. Just put em in there and don't sweat that stuff. You have other things to worry about like whether there is powder in the case or not. Just inspect the primer to make sure it is flush or even a tad bit lower than the bottom of the case. The other 550B hangup you need to watch for is to check the plunger that pushes the primer up into the case. Sometimes powder or other junk gets on top of it or in between the plunger and the primer. You will start to notice dents and if it is even a slim little shiver of brass, lines in your primers. I put my handl forward every once in a while with no case or primer on the plunger and wipe it off.

September 13, 2000, 03:19 PM	#10
Steve Smith Senior Member Join Date: December 9, 1999 Posts: 4,131	Yeah, I'm all over a couple of other sites, too! Sensop, There is no primer return spring on an M14, and I was warned about this with an American Rifleman article that was includedin the paperwork from Springfield.

September 14, 2000, 08:18 PM	#11
johnwill Senior Member Join Date: April 6, 2000 Location: PA Posts: 3,451	The Dillon 550B will seat the primers properly. If there is some reason you really want them recessed, the proper way would be to ream the pocket deeper. Let me be quick to state that I see no reason for that. I've loaded tons of .223 with my Dillon with no primer problems. If you're really worried about the primers, go with a harder primer. I use CCI in the .223, they're one of the harder primers available.

September 16, 2000, 10:10 AM	#12
Patrick Graham Junior member Join Date: January 18, 1999 Location: Kokomo, Indiana USA Posts: 674	You can adjust the primer seating depth on the 550 by moving it out from the edge of the reloading bench. If you upgraded your RL550 to a RL550B you had to move the press out away from the edge of the bench by about 1/8 - 1/4 inch to accomidate the charge bar return plate thickness.

September 17, 2000, 05:53 PM	#13
B9mmHP Senior Member Join Date: February 2, 2000 Location: Texas Posts: 465	Frontsight: You are right about the slam fire. I have done some reasearch on that and found a couple things. But I still recomend the primer pocket reamer. #1 You can have a slam fire if you use the wrong primers.( Soft Primer ) One recomends CCI primers. Another #34 primer did`nt remember the Mfg. #2 You can ream the pocket deeper, but that can weaken the case.