<PAGE>   1
                                                                EXHIBIT 10.31-02
FORM OF SERIES G STOCK OPTION AGREEMENT DATED APRIL 1, 2000
BETWEEN THE COMPANY AND ROBERT F. MECREDY


                         FIREARMS TRAINING SYSTEMS, INC.
                             STOCK OPTION AGREEMENT
                                    SERIES G


Firearms Training Systems, Inc., a Delaware corporation (the "Company"), hereby
grants to Robert Mecredy (the "Optionee") as of April 1, 2000 (the "Option
Date"), pursuant to the provisions of the Firearms Training Systems, Inc. Stock
Option Plan (the "Plan"), a non-qualified option to purchase from the Company
(the "Option") 240,000 shares of its Class A Common Stock, $0.000006 par value
("Stock"), at the price of $0.50 per share upon and subject to the terms and
conditions set forth below. References to employment shall also mean an agency
or independent contractor relationship and references to employment by the
Company shall also mean employment by a Subsidiary. Capitalized terms not
defined herein shall have the meanings specified in the Plan.

1.       Option Subject to Acceptance of Agreement. The Option shall be null and
void unless the Optionee shall accept this Agreement by executing it in the
space provided below and returning such original execution copy to the Company.

2.       Time and Manner of Exercise of Option.


2.1.     Maximum Term of Option. In no event may the Option be exercised, in
whole or in part, after the seventh anniversary of the Option Date (the
"Expiration Date").

2.2. Exercise of Option. (a) Except as otherwise provided in subsections (b)-(d)
or Section 3.5 (relating to a Sale of the Company) below, the Option shall
become exercisable in accordance with the provisions of this Section 2.2(a). For
purposes of this Agreement, Covenant Case EBITDA and Potential Case EBITDA for
each Applicable Fiscal Period (as defined below) shall be defined as follows:

<TABLE>
<CAPTION>
                                 Covenant Case     Potential Case
Applicable Fiscal Period         EBITDA            EBITDA
----------------------------     -------------     --------------
<S>                              <C>               <C>
Quarter Ending 3/31/2001          $  800,000        $ 1,600,000
Fiscal Year Ending 3/31/2002      $1,650,000        $ 5,893,000
Fiscal Year Ending 3/31/2003      $6,257,000        $11,343,000
</TABLE>


For purposes of this Agreement, EBITDA shall have the meaning contained in that
certain Second Amended and Restated Credit Agreement among FATS, Inc., the
financial institutions parties thereto and Bank of America, N.A., as agent,
dated April 1, 2000, as amended, supplemented or otherwise modified. The
Covenant Case EBITDA and Potential Case EBITDA levels set forth above may be
revised by the Board to reflect, in such manner as it deems appropriate and in
each case in its sole discretion, the financial impact of any business acquired
by the Company or FATS, Inc. or otherwise combined with the Company or FATS,
Inc.

(i)      For the fiscal quarter ending March 31, 2001 and each of the fiscal
years ending March 31, 2002 and March 31, 2003 (each, an "Applicable Fiscal
Period"), the Option shall become exercisable as of the last day of the
Applicable Fiscal Period with respect to:

(A)      if the Company's EBITDA for the Applicable Fiscal Period is less than
the Covenant Case EBITDA for such Applicable Fiscal Period, 0 shares;

(B)      if the Company's EBITDA for the Applicable Fiscal Period equals or
exceeds the Potential Case EBITDA for such Applicable Fiscal Period, 80,000
shares; and

(C)      if the Company's EBITDA for the Applicable Fiscal Period equals or
exceeds the Covenant Case EBITDA for such Applicable Fiscal Period but is less
than the Potential Case EBITDA for such Applicable Fiscal Period , the number of
shares determined by adding 40,000 shares to the Ratable Amount of shares for
such Applicable Fiscal Period. For purposes of the foregoing sentence, the
Ratable Amount for each Applicable Fiscal Period shall be determined by
multiplying (I) 40,000 by (II)(a) the Company's EBITDA for such Applicable
Fiscal Period minus the Covenant Case EBITDA for such Applicable Fiscal Period,
divided (b) by the Potential Case EBITDA for such Applicable Fiscal Period minus
the Covenant Case EBITDA for such Applicable Fiscal Period.

The determination regarding the extent to which the Option becomes exercisable
under this Section 2.2(a)(i) for each Applicable Fiscal Period shall be made in
the manner and at the time set forth in Section 2.2(a)(iv).


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(ii)     Subject to Section 2.2(a)(iv), as of March 31, 2003, the Option shall
become exercisable with respect to that number of shares determined by
subtracting the number of shares subject to the Option that have become
exercisable under Section 2.2(a)(i) from the Cumulative Vested Amount (as
defined below); provided however, that if the result is less than 0 shares, it
shall be deemed to equal 0 shares. The Cumulative Vested Amount shall be
determined by multiplying (A) 240,000 by (B)(I) the cumulative EBITDA for the
fiscal quarter ending March 31, 2001 and each of the fiscal years ending March
31 2002 and 2003 (the "Cumulative Vesting Period") minus the cumulative Covenant
Case EBITDA for such period, divided (II) by the cumulative Potential Case
EBITDA for the Cumulative Vesting Period minus the cumulative Covenant Case
EBITDA for such period; provided, however, that the Cumulative Vested Amount
shall in no event exceed 240,000.

The determination regarding the extent to which the Option becomes exerciseable
under this Section 2.2(a)(ii) for the Cumulative Vesting Period shall be made in
the manner and at the time set forth in Section 2.2(a)(iv).

(iii)    Any shares of Stock subject to the Option that do not become
exercisable in accordance with the provisions of this Section or Section 3.5
shall terminate on the earlier of the Optionee's termination of employment or
the third anniversary of the Option Date.

(iv)     For purposes of this Section 2.2(a), the determination as to whether
the requisite EBITDA has been achieved shall be made following the receipt by
FATS, Inc. of its audited financial statements for the years containing or
constituting the Applicable Fiscal Periods.

(b)      If the Optionee terminates employment with the Company by reason of
Disability, the Option shall be exercisable only to the extent it is exercisable
on the effective date of the Optionee's termination of employment and may
thereafter be exercised by the Optionee or the Optionee's Legal Representative
until the earlier of the first anniversary of the Optionee's termination of
employment and the Expiration Date.

(c)      If the Optionee's employment with the Company terminates by reason of
the Optionee's death, the Option shall be exercisable only to the extent it is
exercisable on the date of death and may thereafter be exercised by the
Optionee's Legal Representative or Permitted Transferees, as the case may be,
until the earlier of the first anniversary of the Optionee's death and the
Expiration Date.

(d)      If the Optionee's employment with the Company terminates for any reason
other than as described in subsection (b) or (c) above, the Option shall be
exercisable only to the extent it is exercisable on the effective date of the
Optionee's termination of employment and may thereafter be exercised by the
Optionee or the Optionee's Legal Representative until and including the earliest
to occur of (i) the date which is 90 days after the effective date of the
Optionee's termination of employment and (ii) the Expiration Date; provided that
if the Optionee's employment is terminated by the Company for Cause, the Option
shall terminate automatically on the date the Board authorizes the Optionee's
termination for Cause, and the Optionee shall be subject to the provisions of
Section 2.5.

(e)      For purposes of this Agreement, "Cause" shall have the meaning
contained in Section 4(c) of the Employment Agreement between the Optionee and
FATS, Inc. dated November 1, 2000 (the "Employment Agreement").

2.3.     Method of Exercise. Subject to the limitations set forth in this
Agreement, the Option may be exercised by the Optionee (1) by giving written
notice to the Company on the form provided by the Company specifying the number
of whole shares of Stock to be purchased and accompanied by payment therefor in
full (or arrangement made for such payment to the Company's satisfaction) either
(i) in cash, (ii) by delivery of previously owned whole shares of Stock (which
the Optionee has held for at least six months prior to the delivery of such
shares or which the Optionee purchased on the open market and in each case for
which the Optionee has good title, free and clear of all liens and encumbrances)
having a Fair Market Value, determined as of the date of exercise, equal to the
aggregate purchase price payable pursuant to the Option by reason of such
exercise, (iii) in cash by a broker-dealer acceptable to the Company to whom the
Optionee has submitted an irrevocable notice of exercise or (iv) a combination
of (i), (ii) and (iii), and (2) by executing such documents as the Company may
reasonably request. The Committee shall have sole discretion to disapprove of an
election pursuant to any of clauses (ii) - (iv). Any fraction of a share of
Stock which would be required to pay such purchase price shall be disregarded
and the remaining amount due shall be paid in cash by the Optionee. No
certificate representing a share of Stock shall be delivered until the full
purchase price therefor has been paid.

2.4.     Termination of Option. (a) In no event may the Option be exercised
after it terminates as set forth in this Section 2.4. The Option shall
terminate, to the extent not exercised pursuant to Section 2.3 or earlier
terminated pursuant to Section 2.2 or Section 2.5, on the Expiration Date.

(b)      In the event that rights to purchase all or a portion of the shares of
Stock subject to the Option expire or are exercised, cancelled or forfeited, the
Optionee shall, upon the Company's request, promptly return this Agreement to
the Company for full or partial cancellation, as the case may be. Such
cancellation shall be effective regardless of whether the Optionee returns this
Agreement. If the Optionee continues to have rights to purchase shares of Stock
hereunder, the Company shall, within 10


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business days of the Optionee's delivery of this Agreement to the Company,
either (i) mark this Agreement to indicate the extent to which the Option has
expired or been exercised, cancelled or forfeited or (ii) issue to the Optionee
a substitute option agreement applicable to such rights, which agreement shall
otherwise be substantially similar to this Agreement in form and substance.

2.5      Termination of Option and Forfeiture of Option Gain. (a) If the Board
determines in its sole discretion that the Optionee has breached the covenants
contained in Sections 6, 7, 8, 9, or 10 of the Employment Agreement or the
Optionee is terminated for Cause, then (i) the Option shall terminate
automatically on the date the Board determines that the Optionee has breached
any such covenant or authorizes the Optionee's termination for Cause (as
applicable), (ii) within five business days of receipt by the Optionee of a
written demand from the Company or FATS, Inc., the Optionee shall sell to the
Company or FATS, Inc. (at the Company's election) any shares of Stock acquired
and held by the Optionee (or on the Optionee's behalf) as a result of the
exercise of the Option for a per share price equal to the lesser of (A) the Fair
Market Value of a share of Stock on the date the Board makes such determination
or the date the Optionee is notified of his termination for Cause by the Company
(as applicable), and (B) $0.50; and (iii) within five business days of receipt
by the Optionee of a written demand from the Company or FATS, Inc., the Optionee
shall pay the Company or FATS, Inc. (at the Company's election) an amount in
cash equal to the aggregate gain realized by the Optionee upon the sale or sales
of Stock acquired by the Optionee as a result of the exercise of an option
granted under the Plan.

3.       Additional Terms and Conditions of Option.

Nontransferability of Option. The Option may not be transferred by the Optionee
other than (i) by will or the laws of descent and distribution or pursuant to
beneficiary designation procedures approved by the Company or (ii) as otherwise
permitted under Rule 16b-3 under the Exchange Act. Except to the extent
permitted by the foregoing sentence, during the Optionee's lifetime the Option
is exercisable only by the Optionee or the Optionee's Legal Representative.
Except to the extent permitted by the foregoing, the Option may not be sold,
transferred, assigned, pledged, hypothecated, encumbered or otherwise disposed
of (whether by operation of law or otherwise) or be subject to execution,
attachment or similar process. Upon any attempt to so sell, transfer, assign,
pledge, hypothecate, encumber or otherwise dispose of the Option, the Option and
all rights hereunder shall immediately become null and void.

3.2.     Investment Representation and Restrictions. The Optionee hereby
represents and covenants that (a) any share of Stock purchased upon exercise of
the Option will be purchased for investment and not with a view to the
distribution thereof within the meaning of the Securities Act of 1933, as
amended (the "Securities Act"), unless such purchase has been registered under
the Securities Act and any applicable state securities laws; (b) any subsequent
sale of any such shares shall be made either pursuant to an effective
registration statement under the Securities Act and any applicable state
securities laws, or pursuant to an exemption from registration under the
Securities Act and such state securities laws; (c) to the extent required by an
agreement between one or more underwriters and the Company in connection with an
offering of shares of Stock pursuant to a registration statement under the
Securities Act, the Optionee shall not offer, sell, contract to sell or
otherwise dispose of any shares of Stock purchased upon exercise of the Option
for the period specified in such agreement; and (d) if requested by the Company,
the Optionee shall submit a written statement, in form satisfactory to the
Company, to the effect that such representation (x) is true and correct as of
the date of purchase of any shares hereunder or (y) is true and correct as of
the date of any sale of any such shares, as applicable. As a further condition
precedent to any exercise of the Option, the Optionee shall comply with all
regulations and requirements of any regulatory authority having control of or
supervision over the issuance or delivery of the shares and, in connection
therewith, shall execute any documents which the Board or the Committee shall in
its sole discretion deem necessary or advisable.

3.3.     Withholding Taxes. (a) As a condition precedent to the delivery of
Stock upon exercise of the Option, the Optionee shall, upon request by the
Company, pay to the Company in addition to the purchase price of the shares,
such amount of cash as the Company may be required, under all applicable
federal, state, local or other laws or regulations, to withhold and pay over as
income or other withholding taxes (the "Required Tax Payments") with respect to
such exercise of the Option. If the Optionee shall fail to advance the Required
Tax Payments after request by the Company, the Company may, in its discretion,
deduct any Required Tax Payments from any amount then or thereafter payable by
the Company to the Optionee.

(b)      The Optionee may elect to satisfy his or her obligation to advance the
Required Tax Payments by any of the following means: (1) a cash payment to the
Company pursuant to Section 3.3(a), (2) delivery to the Company of previously
owned whole shares of Stock (which the Optionee has held for at least six months
prior to the delivery of such shares or which the Optionee purchased on the open
market and in each case for which the Optionee has good title, free and clear of
all liens and encumbrances) having a Fair Market Value, determined as of the
date the obligation to withhold or pay taxes first arises in connection with the
Option (the "Tax Date"), equal to the Required Tax Payments, (3) authorizing the
Company to withhold whole shares of Stock which would otherwise be delivered to
the Optionee upon exercise of the Option having a Fair Market Value, determined
as of the Tax Date, equal to the Required Tax Payments, (4) a cash payment by a
broker-dealer acceptable to the Company to whom the Optionee has submitted an
irrevocable notice of exercise or (5) any combination of (1), (2) and (3). The
Committee shall have sole discretion to disapprove of an election pursuant to
any of clauses (2)-(5); provided,


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however, that if the Optionee exercises the option on the Expiration Date, is
employed as of such date, and the shares of Stock are not traded on a national
securities exchange or are not quoted on the Nasdaq National Market as of such
date, the Company shall take reasonable efforts to permit an Optionee to use, in
whole or in part, the method described in clause (3) above. Shares of Stock to
be delivered or withheld may not have a Fair Market Value in excess of the
minimum amount of the Required Tax Payments. Any fraction of a share of Stock
which would be required to satisfy any such obligation shall be disregarded and
the remaining amount due shall be paid in cash by the Optionee. No certificate
representing a share of Stock shall be delivered until the Required Tax Payments
have been satisfied in full.

3.4.     Adjustment. In the event of any stock split, stock dividend,
recapitalization, reorganization, merger, consolidation, combination, exchange
of shares, liquidation, spin-off or other similar change in capitalization or
event, or any distribution to holders of Stock other than a regular cash
dividend, the number and class of securities subject to the Option and the
purchase price per security shall be appropriately adjusted by the Committee
without an increase in the aggregate purchase price. If any adjustment would
result in a fractional security being subject to the Option, the Company shall
pay the Optionee, in connection with the first exercise of the Option occurring
after such adjustment, an amount in cash determined by multiplying (i) the
fraction of such security (rounded to the nearest hundredth) by (ii) the excess,
if any, of (A) the Fair Market Value on the exercise date over (B) the exercise
price of the Option. The decision of the Committee regarding any such adjustment
shall be final, binding and conclusive.

3.5.     Sale of the Company. (a) Notwithstanding any provision in this
Agreement, in the event of the occurrence of a Sale of the Company (as defined
below) after March 31, 2001 and on or before March 31, 2003, this Option shall
become exercisable (to the extent not already exercisable) under the provisions
of Section 2.2(a)(ii) determined as if the Cumulative Vesting Period commences
on January 1, 2001 and ends on the March 31 most recently preceding the
occurrence of the Sale of the Company.

(b)      "Sale of the Company" shall mean any transaction pursuant to which all
of the shareholders of the Company receive cash or Marketable Securities in
exchange for all of each such shareholder's shares of Stock. For purposes of the
foregoing, "Marketable Securities" shall mean stock or other securities that are
determined by the Board in its good faith discretion to be readily saleable by
the shareholders of the Company (subject to any lock-up restrictions that are
determined by the Board, in its sole discretion, to be reasonable) without
causing a significant discount or decrease in the price of such securities.

3.6.     Compliance with Applicable Law. The Option is subject to the condition
that if the listing, registration or qualification of the shares subject to the
Option upon any securities exchange or under any law, or the consent or approval
of any governmental body, or the taking of any other action is necessary or
desirable as a condition of, or in connection with, the purchase or delivery of
shares hereunder, the Option may not be exercised, in whole or in part, unless
such listing, registration, qualification, consent or approval shall have been
effected or obtained, free of any conditions not acceptable to the Company. The
Company agrees to use reasonable efforts to effect or obtain any such listing,
registration, qualification, consent or approval.

3.7.     Delivery of Information to Optionee. The Company shall forward to the
Optionee annual reports to shareholders and annual or quarterly financial
statements of the Company, including the consolidated balance sheet and related
consolidated statements of operations and cash flows for a fiscal year, fiscal
quarter or period of a fiscal year, as applicable, as soon as administratively
practicable after such materials are prepared and distributed or filed, as the
case may be, by the Company. The Optionees shall have the same rights as holders
of shares of Stock to notice with respect to annual or special meetings of
shareholders of the Company, and shall have the right to attend any such
meetings.

3.8.     Delivery of Certificates. Upon the exercise of the Option, in whole or
in part, the Company shall deliver or cause to be delivered one or more
certificates representing the number of shares purchased against full payment
therefor. The Company shall pay all original issue or transfer taxes and all
fees and expenses incident to such delivery, except as otherwise provided in
Section 3.3.

3.9.     Option Confers No Rights as Stockholder. The Optionee shall not be
entitled to any privileges of ownership with respect to shares of Stock subject
to the Option unless and until purchased and delivered upon the exercise of the
Option, in whole or in part, and the Optionee becomes a stockholder of record
with respect to such delivered shares; and the Optionee shall not be considered
a stockholder of the Company with respect to any such shares not so purchased
and delivered.

3.10.    Option Confers No Rights to Continued Employment. In no event shall the
granting of the Option or its acceptance by the Optionee give or be deemed to
give the Optionee any right to continued employment by the Company or any
affiliate of the Company.

3.11.    Decisions of Board or Committee. The Board or the Committee shall have
the right to resolve all questions which may arise in connection with the Option
or its exercise. Any interpretation, determination or other action made or taken
by the Board or the Committee regarding the Plan or this Agreement shall be
final, binding and conclusive.


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3.12.    Company to Reserve Shares. The Company shall at all times prior to the
expiration or termination of the Option reserve and keep available, either in
its treasury or out of its authorized but unissued shares of Stock, the full
number of shares subject to the Option from time to time.

3.13.    Agreement Subject to the Plan. This Agreement is subject to the
provisions of the Plan and shall be interpreted in accordance therewith. The
Optionee hereby acknowledges receipt of a copy of the Plan.

4.       Miscellaneous Provisions.

4.1.     Designation as Nonqualified Stock Option. The Option is hereby
designated as not constituting an "incentive stock option" within meaning of
section 422 of the Internal Revenue Code of 1986, as amended (the "Code"); this
Agreement shall be interpreted and treated consistently with such designation.

4.2.     Meaning of Certain Terms. (a) As used herein, employment by the Company
shall include employment by an affiliate of the Company. References in this
Agreement to sections of the Code shall be deemed to refer to any successor
section of the Code or any successor internal revenue law.

(b)      As used herein, the term "Legal Representative" shall include an
executor, administrator, legal representative, guardian or similar person and
the term "Permitted Transferee" shall include any transferee (i) pursuant to a
transfer permitted under Section 3.4 of the Plan and Section 3.1 hereof or (ii)
designated pursuant to beneficiary designation procedures approved by the
Company.

4.3.     Successors. This Agreement shall be binding upon and inure to the
benefit of any successor or successors of the Company and any person or persons
who shall, upon the death of the Optionee, acquire any rights hereunder in
accordance with this Agreement or the Plan.

4.4.     Notices. All notices, requests or other communications provided for in
this Agreement shall be made, if to the Company, to Firearms Training Systems,
Inc., 7340 McGinnis Ferry Road, Suwanee, Georgia 30174, Attention: Corporate
Secretary, and if to the Optionee, to the Optionee c/o Firearms Training
Systems, Inc., 7340 McGinnis Ferry Road, Suwanee, Georgia 30174. All notices,
requests or other communications provided for in this Agreement shall be made in
writing either (a) by personal delivery to the party entitled thereto, (b) by
facsimile with confirmation of receipt, (c) by mailing in the United States
mails to the last known address of the party entitled thereto or (d) by express
courier service. The notice, request or other communication shall be deemed to
be received upon personal delivery, upon confirmation of receipt of facsimile
transmission or upon receipt by the party entitled thereto if by United States
mail or express courier service; provided, however, that if a notice, request or
other communication sent to the Company is not received during regular business
hours, it shall be deemed to be received on the next succeeding business day of
the Company.

4.5.     Governing Law. This Agreement, the Option and all determinations made
and actions taken pursuant hereto and thereto, to the extent not governed by the
laws of the United States, shall be governed by the laws of the State of
Delaware and construed in accordance therewith without giving effect to
principles of conflicts of laws.

4.6.     Counterparts. This Agreement may be executed in two counterparts each
of which shall be deemed an original and both of which together shall constitute
one and the same instrument.


FIREARMS TRAINING SYSTEMS, INC.



By:
   -----------------------------------
   Name:
   Title:

Accepted this _______ day of _________________, 2000.



Optionee



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