Sunday, December 6, 2009

Headspace

CZ from B&BS armoury

Apologies to all but I've badly neglected the gun side of things; so here's some headspace technics from Tom at Boomers - no mean info for those, like me, who enjoy milsurp rifles and more importantly shooting them. Thanks mate; you'll be glad to know I made the effort to get my Lee's headspace checked by a 'smith...

A lot of people think they understand headspace, but they really don't. Even a lot of gunsmiths, reloaders, and otherwise intelligent people. The Parson asked me if I might be interested in writing a guest bit and I thought this is something that would be worth addressing as there are so many mythical ideas out there. Static headspacing is pretty simple, either the cartridge chambers within .001-3" of chamber print for cartridge or it doesn't. There are many problems, though, with this simplistic view of headspace. I shall attempt to address them in detail.

To simplify things, we shall assume that all cartridges are exactly the proper over-all length, which is of course not true with any factory ammo. We shall also assume that the chamber throating has been properly done. Also a falsehood in 99.9% of factory barrels.

First off, SAAMI specs are sloppy. Going by field gauges and go and no-go gauges will keep your case from rupturing, which is a good thing, but it isn't much of a path to accuracy or precision. Gauges generally accept .005-.006", I don't. You will see why this is important shortly.

Headspace is not a static thing in the firing of any kind of metallic cartridge firearm for a number of reasons. First off, there are the variable of action strength, design, and metallurgy. Break action guns are the springiest and falling block and interrupted thread artillery style breeches (almost never seen on small arms any more) are the stoutest. Therefore starting with perfect or near perfect headspace in a static sense in break action guns is especially critical. The weaker the action the more critical it is to get things right. Blowback semi-autos, delayed or not, also are sensitive not only in accuracy but in probability of misfire if headspacing is not correct.

When you have chambered a round in your firearm with a proper OAL cartridge and SAAMI acceptable static headspace all is apparently well. What goes un-noticed is what actually happens when you press the trigger and fire the round, as it's not directly observable under normal conditions in most types of firearms. When the hammer drops/striker moves forward and the primer is whacked, you are hammering SHARPLY AND VERY HARD on the primer if all is well. The denting of the primer cup absorbs much, but not all of this energy. You are whacking a tube of thin, soft, brass (varying in those properties somewhat depending on how it was annealed and if it has work hardened or not) and more gives than just the dent in the primer. We assumed proper OAL and chamber but keep in mind for reliability: If the chamber is wrong or the OAL is wrong, or both, you may get a misfire beause the primer strike mostly punted the cartridge forward in the chamber and you got a light primer strike resultant of that.

Break open guns have a great virtue for examining the results of this because as my amigo Mike Bellm of Bellm TCs has said many a time, "You CAN DIRECTLY not only SEE what happens, BUT you can also measure the results." He and I have discussed this many a time regarding accuracy and misfires, He is lucky enough to be working with BPI/CVA/Bergara Barrels on product designs and manufacturing methods and recently was over in Spain working with the Bergara Barrel Factory. In a recent email from Mike, he mentioned:

This today from the head tech at BPI/CVA/Bergara that I work with regularly and who took me to the Bergara plant in Spain the first of last month:

"I don't remember if I mentioned it to you or not but I dropped some loaded .35 Whelen rounds in a barrel and measured from the breech to the ctg base.

Average about .005". This was very consistent through this partial box. I
then dropped in a few misfired rounds that had been hit by the firing pin.
The average measurement went from .005" to .014"! Proof enough for me to
believe that the blow of the firing pin is crushing the shoulder."

..... and I have to add, all the more reason for YOU to be able to take the measurements and find these things for yourself, then make your own corrections as necessary.

That is a total collapse of .009" at the shoulder!


Rather interesting, is that not? Belts on belted magnums provide some insurance against such behavior, provided the belt is properly placed on the cartridge and the chamber is properly cut for the belt, which is not always true. I've gotten
A-Square brass where the belt was misplaced significantly. I'm naming them directly here because if you Google their brass prices for safari rifle cartridge brass alone, not cartridges, you can see why it was vexing when they refused to talk to me about possibly replacing it with dimensionally correct brass. Didn't answer the phone messages or emails. Belts .008-.011 short of appropriate forward bearing surface are not acceptable and are of no use but scrap/example of shoddy product. I know this is a Christian page but some things aren't very forgivable if you wish to remain in business. Anyway, if the belt is wrong or the chamber isn't cut properly for the belt, your headspace will be variable dynamically even with a belted magnum designed to prevent case movement and assure proper headpsace because it will be headspacing via projectile on the chamber throat/barrel leade and/or case mouth and/or shoulder. Rimmed cartridge movement is primarily determined by the strength of the rim, provided the chamber and OAL are correct and the counterbore for the rim is correct.

So, you see why .001-.002' of headspace is a good idea for consistent shooting now? Dynamically, your acceptable static headpace very well may not be acceptable.

You can test your own firearms by loading empty cartridges with deactivated primers to correct OAL and "firing them". Then you'll know how much variation there is in the brass you are using/whether or not there are chamber issues. Then fix what needs to be fixed, if you find much variation. You'll make misfires very unlikely and gain accuracy.

Remember, mi amigos, all firearms may be interesting, but only accurate firearms are particularly interesting for anything but hanging on the wall and making loud noises.

Happy Shooting.


And a blessed Advent,

LSP

Thursday, December 3, 2009

Day in the Country


Got to the Stables early and the barn cats galloped for their food; you' think they were starving, which they aren't. Regardless, it was neat to watch them race across the grass and better still to approximate to the same thing on horseback.

galloping cat

Later in the day, towards dusk, the air filled with birds - a cacophony of the things, fiercely strutting about and pecking for food. There must have been hundreds of them around the parsonage; incredibly noisy but interesting to watch.


After watching them carry on for a time I drove off to say Mass and was a little worried to see several pews full of silent, reverent people when I arrived at the church. Was I late?! No, they were just keen and intent on saying their prayers. I love that.

You'll forgive me for not commenting on the unfolding Warmist scandal, yet more attacks by Muslim 'martyrs', Episcopal priests praying to Aztec 'saints' (and Muslim martyrs) and a strange old woman in the diocese of D.C. who celebrated a neo-pagan 'Croning' liturgy in the National Cathedral. More of that anon.

Keep pulling the trigger.

LSP

Friday, November 27, 2009

Bad Laterals, Worse Science Czar

For some strange reason the Texas flag was missing at the Stables but that didn't put me off riding too much. Cantered about for a bit and worked, mostly unsuccessfully, at Laterals. As you'd expect, this is when you get the horse to go forward at an angle, or in my case get it to go in circles, annoyingly. Shot quite well though, which is always satisfying.

Interesting to note that 'Climategate' or 'Warmaquiddick' is picking up steam, not least with "Lift up a rock and another snake comes slithering out" John Holdren's involvement. Holdren's our 'Science Czar'; he's a Soylent Greener eugenicist in favor of forced abortions and sterilization. Just how many of these wicked Sangerites are in power here?

Terrifying.

Shoot straight.

LSP

Thursday, November 26, 2009

Happy Thanksgiving


Drove to Durant Oklahoma today with Ma LSP and two of the sisters. 'Why?' you ask. Because my mother's family used to have a house and a ranch there and we wanted to revisit the place. It was good; Durant has the world's largest peanut, a Confederate war memorial,


and nearby Lake Texoma, where my grandfather liked to eat. The Lake Resort's abandoned now. I found it haunting.


Then it was back to Dallas after lunch; a beautiful day and good to get out of town.

So, happy Thanksgiving to all and God bless,

LSP

Tuesday, November 24, 2009

Posh Guns



Interesting visit to a member of the legal profession in Dallas viz. probating a will - interesting because he had an immaculate collection of Lee Enfields, Mausers and the odd American .30 in his office. A Texan variant, I suppose, of magazines in the dentist's waiting room and altogether more enjoyable - to me, anyway. After that it was a trip to the Beretta Gallery in Highland Park and a gaze at shotgun's I'll never be able to afford; beautiful bits of kit for the wealthy shooter and, at the 'doable' end of the spectrum, lots of Tikka/Sako variants. Didn't buy anything but it was uplifting to be in the proximity.

Then of course there's Climategate; ten out of ten Soylent Green points for fraudulent 'science' and a terrifying vision of, er, present day reality.


Don't eat those wafers, chaps - eat BBQ instead, better for you.

LSP

Friday, November 20, 2009

Stock Tank Plinker


Finally broke free of Dallas and headed off to the country, where it smells better, you can ride arabian horses and plink about at stock tanks, which is what I did.

Good to get back on the horses, though the one I was riding seemed to think she was through about half way through the ride... some say this is common. Regardless, she changed her mind and we had a good canter about. Most enjoyable.

Afterwards stopped at a roadside Mexican place called 'Karen's', oddly. Senora Karen served an excellent brisket and bean tortilla; I never knew there was such a thing - and now I'm glad I do.

More seriously, and you'll forgive me for dredging up old news, but why is it that the MSM near enough refuse to acknowledge religious motivation to the Fort Hood shooter? Are they right to do this? Perhaps they're being 'strategic' and acting in some veiled kind of way to defend the country? Again, maybe shouting the Islamic war cry before killing people has nothing to do with religion. Or is it simply the case that we've lost confidence in our culture to such an extent that we're unable to rise to the challenge of an ideology implacably opposed to ours and pretend it just isn't there.

Forgive the lack of levity, on a happier note, have a blessed Feast of St. Edmund.

Shoot straight,

LSP

Friday, November 13, 2009

Archdruid of Canterbury

photo thanks to All Seeing Eye & GOT here

From the Daily Mail:

"The Archbishop of Canterbury last night admitted the future of the Church of England was 'chaotic and uncertain'. Rowan Williams said 'God knows' what will happen amid attempts by the Vatican to lure Anglican clergy to convert to Roman Catholicism."


Well go figure, ++Rowan, spiritual heir to Augustine, druid, dhimmi, sharia endorsing writer of incomprehensible theology and all round Anglo-Catholic sell out. But hold on, something's wrong with the list - ah yes, the Augustine bit.


Lets see how many in the U.K. swim the Tiber for Rome, maybe few but I'd be surprised if trads are staying in out of love for their leader.


Guns tomorrow.


LSP


Wednesday, November 11, 2009

Veterans Day


“Never give in - never, never, never, never, in nothing great or small, large or petty, never give in except to convictions of honor and good sense. Never yield to force; never yield to the apparently overwhelming might of the enemy.” - Winston Churchill

I'd say Churchill's words ring true today and, to all those who were and are prepared to sacrifice their lives for our common good, respect, honor and prayers.

LSP

Tuesday, November 10, 2009

Say No To Nanny


Found this picture on the excellent Free Canuckistan site and thought it amusing, so what can we say but Free Mark Steyn.

Busy trying to catch up on the news and clarify thoughts on the recent Apostolic Constitution for Anglican converts to Rome but more of that anon. In the meanwhile, badly in need of a good fix of Horse & Gun.

Shoot straight,

LSP

Sunday, November 8, 2009

Friday, November 6, 2009

God Bless Sgt. Munley


From Boomers & BS:

"Sgt. Munley was one of the "first responders" who returned fire after army psychiatrist Maj. Nidal Malik Hasan went on the rampage at the sprawling Fort Hood base in Texas. She shot Hasan four times but was herself wounded in the gun battle. Her condition is now stable, according to military officials."

Pray that Sgt. Munley makes a full recovery. Pray too that we wake up to the reality of the Jihad.

I won't comment, other than to thank Tom for his post, but I will leave you with these lines from the religion of peace.

"Fight those who do not believe in Allah, nor in the latter day, nor do they prohibit what Allah and His Messenger have prohibited, nor follow the religion of truth... until they pay the tax in acknowledgment of superiority and they are in a state of subjection." (Koran 9:29)

The world needs to wake up to the above, not least the United States.

LSP

Wednesday, November 4, 2009

Church n State


I just learned something new from Old Lightning about the Washington Monument; it has the words Laus Deo inscribed on its top. There's more, which I'll reproduce, again thanks to Old Lightning, it's a bit long but worth the read. Make of it what you will:

"One detail that is never mentioned is that in Washington , D.C. there can never be a building of greater height than the Washington Monument.

With all the uproar about removing the ten commandments, etc., this is worth a moment or two of your time. I was not aware of this amazing historical information.

On the aluminum cap, atop the Washington Monument in Washington , D.C. , are displayed two words: Laus Deo.

No one can see these words.. In fact, most visitors to the monument are totally unaware they are even there and for that matter, probably couldn't care less.

Once you know Laus Deo's history , you will want to share this with everyone you know. These words have been there for many years; they are 555 feet, 5.125 inches high, perched atop the monument, facing skyward to the Father of our nation, overlooking the 69 square miles which comprise the District of Columbia, capital of the United States of America .

Laus Deo! Two seemingly insignificant, unnoticed words. Out of sight and, one might think, out of mind, but very meaningfully placed at the highest point over what is the most powerful city in the most successful nation in the world.

So, what do those two words, in Latin, composed of just four syllables and only seven letters, possibly mean? Very simply, they say ' Praise be to God!'

Though construction of this giant obelisk began in 1848, when James Polk was President of the United States, it was not until 1888 that the monument was inaugurated and opened to the public. It took twenty-five years to finally cap the memorial with a tribute to the Father of our nation, Laus Deo 'Praise be to God!'

From atop this magnificent granite and marble structure, visitors may take in the beautiful panoramic view of the city with its division into four major segments. From that vantage point, one can also easily see the original plan of the designer, Pierre Charles l'Enfant ..a perfect cross imposed upon the landscape, with the White House to the north. The Jefferson Memorial is to the south, the Capitol to the east and the Lincoln Memorial to the west.

A cross you ask? Why a cross? What about separation of church and state? Yes, a cross; separation of church and state was not, is not, in the Constitution. So, read on. How interesting and, no doubt, intended to carry a profound meaning for those who bother to notice.

Praise be to God! Within the monument itself are 898 steps and 50 landings. As one climbs the steps and pauses at the landings the memorial stones share a message.

* On the 12th Landing is a prayer offered by the City of Baltimore ;
* on the 20th is a memorial presented by some Chinese Christians;
* on the 24th a presentation made by Sunday School children from New York and Philadelphia quoting Proverbs 10:7, Luke 18:16 and Proverbs 22:6. Praise be to God!

When the cornerstone of the Washington Monument was laid on July 4th, 1848 deposited within it were many items including the Holy Bible presented by the Bible Society. Praise be to God! Such was the discipline, the moral direction, and the spiritual mood given by the founder and first President of our unique democracy 'One Nation, Under God.'

I am awed by Washington 's prayer for America Have you ever read it? Well, now is your unique opportunity, so read on!

' Almighty God; We make our earnest prayer that Thou wilt keep the United States in Thy holy protection; that Thou wilt incline the hearts of the citizens to cultivate a spirit of subordination and obedience to government; and entertain a brotherly affection and love for one another and for their fellow citizens of the United States at large. And finally that Thou wilt most graciously be pleased to dispose us all to do justice, to love mercy, and to demean ourselves with that charity, humility, and pacific temper of mind which were the characteristics of the Divine Author of our blessed religion, and without a humble imitation of whose example in these things we can never hope to be a happy nation. Grant our supplication, we beseech Thee, through Jesus Christ our Lord. Amen.'

Laus Deo!

When one stops to observe the inscriptions found in public places all over our nation's capitol, he or she will easily find the signature of God, as it is unmistakably inscribed everywhere you look. You may forget the width and height of 'Laus Deo', its location, or the architects but no one who reads this will be able to forget its meaning, or these words: 'Unless the Lord builds the house its builders labor in vain. Unless the Lord watches over the city, the watchmen stand guard in vain.' (Psalm 127: 1)"

Perhaps the monument should be banned, just like crucifixes in Italian schools, or the 10 Commandments, or Christianity in Camden.

Laus Deo,

LSP